Does Makita multi-tool DTM51 have a real Starlock mount

No
Your multitool does not have a Starlock mount.  But some Starlock blades are compatible nonetheless.
Starlock
Starlock has three types of blades: Starlock regular, Starlock Plus, and Starlock Max.  The latter are more sturdy.

All Starlock blades are 3D-curved; they have a bulge. The three sub-types differ only in the cutouts.

DTM51 is not Starlock
Your Makita DTM51's mount is not curved, so it's not StarLock.

A 'real' Starlock mount has an inverse bulge like this:

And Makita is starting to sell these too.  See the new Starlock Max DTM52.

Compatibility
Your multitool can however accept some Starlock blades when these blades are backwards compatible with 'flat' heads.
For example, cutouts in the shape of Bosch OIS (Oscillating multitool Interface System) may be present.
Typically, Starlock Plus or Max blades will not have OIS cutouts because they support larger forces for which Starlock was developed.


If you are going to spend a bunch of money on HVAC for a vacant house, 50% (or "between 40 and 60%")

Else, drain the plumbing, put RV antifreeze in the sink and toilet traps, turn off the furnace and let the humidity be what it is. Far less costly for 5 months.


Replacing electrical wiring in masonry walls

If the wiring is in conduit you should be able to remove it without damaging the walls. If the wiring is by some other method you will not be able to remove the wiring without demolishing the wall or major repair work.


When snaking the main sewer line, how do you know when you've reached the street connection?

I've done this a few times and I've never been able to "feel" when you hit the street. Maybe someone who does this often acquires more of a feel. I'm at least 50ft from my street, so perhaps it's just because there's a lot of resistance from the 50ft of snake in the line.

The easiest way (other than a camera of course) to know you're at the street is to measure the distance from the edge of your foundation to the street, then add the distance inside plus a few feet to account for it not being perfectly straight and level. If you've gone 70ft when you think it should only be 50ft, my guess is that you're past the street already.  Either that or the markings are wrong.


How can I transition between rooms when refinishing hardwood floors?

I think that if you could make sure the stain/varnish colors match by refinishing both floors together, that would be your best bet. Unless the wood floors were installed at different times and have different grains/widths. In that case, no matter what you do the transition will be apparent.

If that that's the case, you might be able to do something decorative, with ornate wood squares or with tile, especially if you do it multiple areas of your house so that it echos the accent in more than one place. I know this is not the unobtrusive look you hoped for, but it could still look very pretty. If your kitchen uses small tiling, or if you have a fireplace with stone or tiling, or if you have any brick walls, you might be able to do a thin band of the same tiling/brick in the doorways, complemented by a border of the tiling/brick beneath your front door. See http://www.pinterest.com/pin/377739487469141226/  and  http://www.pinterest.com/pin/383368987001982461/.


What happens if CT ratio entered wrong in 3phase meter

If your meter is assuming one ratio, and it's actually a different ratio, then the meter will read incorrectly.


It is Grohe model 29733

How I found it...

After weeks of searching, I stumbled on a picture of a diverter handle that has the same icons for shower and hand-held positions that my handle has (see the third picture in the original question). Knowing that the handle in that picture was made by Grohe, I started searching Grohe's website and found an almost identical diverter (based on the parts I can see). The only thing that is different is the length of the knurled part of the stem.

Grohe 2-Way Diverter Rough-In Valve Model 29712000

Armed with this knowledge, I used the WayBack Machine to find an older model.


How do I prevent water from collecting against side of house?

If the cost of raising the patio is too great you could get an angle grinder or perhaps a better choice would be renting a concrete wet saw and cut out a strip about 6 inches wide from the edge that meets the house wall. As @woodchips points out in his comment, make sure you wear gloves, safety goggle and a mask for this. It'll get hot, but it's very dusty work and the saw will throw up chips of concrete.

Remove all the concrete and put in a gutter that will collect the water and direct it away from the house to the drains.


How to tell when a plumbing fitting is tightened correctly?

Compression fittings do not use tape, so that's one mistake to fix. Tape seals a leak in threads, but a compression fitting is sealed at the ferrule, not at the threads. Leaks are frequently caused by over tightening, so this is certainly a possibility in your situation. Here are my suggestions:

Replace the nut and ferrule. The ferrule gets deformed when compressed, so a new ferrule won't have the deformations from the previous valve.
Hand tighten the assembly, though I typically use a wrench and guess where I could likely get it by hand without destroying my fingers. Add another half turn by wrench.
Test for leaks, and if found, add another quarter to half a turn until the leak stops. By doing this in iterations, you minimize the risk of over tightening. You can always tighten it more if you under tightened it, but once you over tighten, you have to get a new ferrule.


Safe to mount curtain rod to support beam?

It's always smart to ask when dealing with support structures in a building. I'm not an engineer but based on my long experience in dealing with various structural issues attaching screws of that size to the bottom of a 6x8 beam to hang a curtain is not an issue. The assumption, Of course, is that this is a standard curtain and not made of chain mail.


You can overcoat over any old paint if these things are true:

The paint is fully cured (which can take up to a year or two for single-can paints which rely on air or atmospheric moisture to cure.)   Curing is not the same as drying.  Curing is the paint molecules "holding hands", polymerizing into much longer molecules.
You scuff-sand the old paint so the surface has microscopic ridges and valleys ("tooth"), a Scotchbrite pad will suffice, this will remove the gloss from the paint.  Be careful not to blow through corners and ridges.
You clean the surface thoroughly to remove grease, oil, dirt and the like.  Especially important in kitchens!

Classically one might use TSP (Tri-Sodium Phospate) to attempt to both clean greases and etch the surface.

Where does primer enter the picture?

You want a primer over bare material.  Original oil Kilz is high-performing over wood.  It's not the very best; that's a marine 2-part epoxy primer.  Over aluminum or steel you'd want a zinc chromate primer (the classic green color of unpainted aircraft), over steel I just tend to go Rustoleum.
When you have dissimilar surfaces or colors, and you want to normalize them so they don't "print through".
If your topcoat doesn't want to stick to the surface as-is, this is called a barrier coat.

If you don't have any of those situations, a primer may not be needed.

I am no fan of the Kilz latex primer; I feel the oil-based product is far more suitable for wood.  Perhaps the Kilz latex makes sense over drywall; you certainly do need a primer for that.


Basically A is a time clock for B a low voltage transformer.
C looks to be the hot in and D looks to be the hot out from the time clock to switch the low voltage transformer ( which apparently is being direct wired by cutting off the male plug).

Another scenario is the time clock does or used to do high voltage tree lights.  The low voltage transformer used to be plugged into an outlet but is not used anymore.  Just guessing.


How wide of an opening for framing cabinets

People usually assume that framing will be out of plumb and/or not straight, so allow an extra inch or two in the finished opening. That gap gets filled by filler strip that's custom scribed to the opening.


Cheap solution to unscrew and screw back a refillable lighter valve (to clean a lighter)

Go to basement, garage sale, or thrift store and pick up an old, regular screwdriver about the right size to fit the slot in the lighter.
Use a file, hacksaw, angle grinder or mototool type device to cut a slot in the screwdriver. Make the slot big enough to fit around the gas nipple.
Unscrew as needed.


Running conduit for future electrical work

This sounds like a great plan!
If the attic is easily accessible, the inspector should be able to access it to inspect the conduit sticking up there if he's not satisfied with what she can see in the box itself.
Make sure you look at the different vehicles currently available and the in-wall plugs they need, then get conduit big enough for the wiring and a box big enough to hold the largest plug & wiring. I don't know enough about the amps needed and the plugs required to make a suggestion, but they are bigger than your standard 110v outlet.


Purpose of this diagonal board on underside of deck?

It’s a temporary brace...probably used temporarily during construction and they forgot to remove it. (Look close and you’ll see the end of the board is not fastened.)
The height of the deck above the ground has nothing to do with the use (or need) for a brace.


Herringbone flooring from regular laminate

The ratio of length to width needs to be exact to make a herringbone pattern work. The width needs to be an exact multiple of the length. You can check this by laying a row of planks next to a lengthwise plank. Then you can decide if you think it will work by cutting the length of the plank to match.
If this is a floating laminate you'll need to cut off some of the interlocking lip of each laminate plank and figure out if the planks will hold together still. You'll probably be outside of the overlap spec of the manufacturer so warranty will be void. This is very much an advanced layout and your floor needs to be dead flat to have any chance of this working well. Picking a glue down plank will likely yield better results


What is the minimum distance from the floor for a 1/2 bath power outlet?

A receptacle not serving the basin has no height requirement in a dwelling unit, but...
2017 NEC 210.52(D)Bathrooms. At least one receptacle shall be installed in bathrooms within 3 ft of the outside edge of each basin...In no case ...be located more than 12 in. below the top of the basin.
I don't have record of when this was adopted but it isn't highlighted grey in the codebook, so it has been in there since 2014 at least.
I think it may have been possible if the switches are within 3' that there was a receptacle and switch, the switch fed both the light and fan but somebody removed the receptacle to have space to put a timer on the fan. If it is only one circuit in that switchbox and it feeds receptacles outside of this bathroom it wouldn't meet current code. I don't know what the code said when built but modifications are required to meet current code.


Would this solution work with my dehumidifier?

You got a strange problem for an outdoor storage building. A dehumidifier is gonna cost you a mint to run if the moisture problem is that bad.  Two things to think about.  First, where is all this moisture coming from? can you mitigate the source? Second, look at the gables or sofits to see it you can install some good venting. You can put a ridge vent on metal roofs and maybe a couple of gable end vents.  what kind of floor do you have?  A soil floor would be a good source of excessive moisture, or fresh concrete for that mater.  If it is soil, try some 4 or 6 mil plastic sheeting over the ground, then tape or secure it to the walls to block moisture form coming up out of the ground into your building. A fan that blows out of a vent would be a lot cheaper than a dehumidifier.  How about some pictures?  Could help tell the story.  Good Luck.


Can a C wire be used for two thermostats?

I think NO. The C-wire connects to the transformers on the individual units.  It's not like a common neutral or ground wire. You'll need to get a C-wire to both furnaces as there is no real electrical connection between the two on the low voltage side.  There might be other solutions that the "big three" might be able to come up with, but I think your stuck with getting a C wire to each furnace independently.


Crossed neutrals can be fixed depending on where they are crossed.

Start in your main panel. You will need to open the panel. WARNING, there is lethal voltage in there, if you aren't sure of what you are doing in the panel, hire a professional.

Look at both the breakers in question. Follow the hot wire from each breaker and find its corresponding neutral. Where the hot leaves the panel a neutral should enter. Does each breaker have its own neutral? If yes we can move on. If no, you have a common neutral and you should call a professional to fix it or start a new question because you have something that needs to be fixed.

Since we have two neutrals we now need to figure out where they got tied together. You will need to go to every box that either of these circuits passes thru one at a time.

Shut off the circuit whose outlets are closest to your breaker panel (call it circuit 1). Go to each box, you will need to open it up and check for voltage on all the hots going in and out of the box. If you find a hot circuit, confirm that it is circuit 2 by turning it off and checking again. Once we find the hot circuit look at the neutrals in the box they are probably all tied together. That is your problem.

With both circuits off, you will need to figure out which neutrals go to which circuit, and separate them. To be clear when you are done, all neutrals need to have a path back to your main panel.

Good Luck


Is there a safe way to check for a short in a motor (garbage disposal)?

Your equation (Ohm's Law) is correct but you are failing to take into account that the formula you've written is for DC STEADY-STATE conditions.  An INDUCTION MOTOR, which is undoubtedly what you have in your disposal, runs on AC and doesn't follow this limited-case equation.

An induction motor, you can read theory here:

Induction Motor Basics

will look like a low-resistance load at DC.  That, of course, is what you're seeing.  But it's not just a straight wire but rather an inductor so if you apply 60HZ AC to it, you now must account for the DELTA V (i.e. rate of change of the input voltage) to calculate the IMPEDANCE of the load.  Impedance is the actual "resistance" of a complex load to the input power.  Calculating the of an induction motor is fairly complicated since you must include the wiring resistance, the inductance, and as the motor moves, the "back EMF" that it generates.

Long story short: If it blows the circuit breaker when you switch it on, you have a short or other problem in the motor.  If it just hums, you probably have a blocked rotor, and if it doesn't nothing, you may have an open in one of the windings.

  put one of those stupid sideways 20A plugs that nobody uses in the wrong spot

Yes, those ARE used and indicate that this device should be on its own dedicated 20A circuit.  Based on your description, however:

  doing her thing as usual, crammed a bunch of food in the garbage disposal, and ran an extension cord from the plug I installed to a wall outlet. Big surprise, it blew a breaker.

You may have damaged the motor by loading it down and then running it with a poor source of power, specifically the extension cord.

Clear the blockage out of it, see if it has a keyway on the bottom of the unit where you can turn the shaft with a hex wrench, and see if you can get it going again.

If not, time for a new one.  Please either get one that is rated for the power you have or install a proper outlet and circuit for the unit's requirements.


Will snow/water damage my floating deck?

A floating deck is typically, as I understand it, not "lumber on the ground". It is lumber on "Dek Blocks" or similar, with posts as needed (which could be anywhere from nothing (on the highest natural spots) to several inches to a few feet tall) sitting in the Dek Blocks to support the deck frame in a level manner.
A floating deck is definitely a DIY project. It is quite different from a traditional deck: No footings to pour, no critical connection to the house, often no permits required. Permits are almost always required for a traditional deck. For a floating deck, the rules vary by jurisdiction - e.g., in my area (at least when I built my floating deck), no permit required up to 200 square feet.
As far as snow & rain, there are two issues - top and bottom. For the top, make sure that there is enough of a gap between the decking boards for water/melting snow to drain. For the bottom, if the boards are pressure treated and on top of blocks, you should be fine, as the rain and melting snow won't collect underneath. But if you put the frame directly on the patio then you could easily have sections where water would collect and cause problems, even with pressure treated wood.


The biggest issue will be the height difference from the hardwood to laminate and a moulding to cover the transition.  Depending on the height of the hardwood, you are at least looking at a half inch difference (at minimum) between the wood and laminate.  And the moulding might also be a trip hazard for any older people as they enter/leave your house.

My personal choice would be to remove the section of hardwood to remove the above two issues.


Color Temperature, Eye Strain and Headache

First link with an explanation about color temperature, too long to copy here:
http://www.osram.nl/media/resource/hires/333565/light-can-be-white-en.pdf

Basically...

fluorescent tubes x30 are equivalent to halogen light. I installed them in my living room because I like warm light, but warm white (2700 K) was too warm. It will not tire your eyes and won't make you feel too awake at night, so you fall asleep normally
tubes x40 are cheap industrial lighting, warmer than the light outside, but not so warm to make your place feel "home" (yeah this is the best I can go to be short)
tubes x54 are equivalent to outside light, in a bright but not sky-blue day. Not common.
tubes x65 are basically almost blue and equivalent to a day when the sky is without cloud, blue. Not suitable.

The "x" above can be 6, 8, 9. For industrial you use 6, better luminous efficiency, for normal use 8, for specialised work (photo editing/printing studio, expositions, ...) and 8 for the rest.

If you have 840 you should be fine, it's very common. 830 is also common, in my company this is what we use in the offices. I can clearly see that, when the light is on during the day, the office walls close to the entrance appear more reddish/yellowish than the walls closer to the window. But it doesn't matter.

Color-wise you are fine (check also the PDF linked).

If you have old ballasts, they run at 100 Hz and you may unconsciously see some flickering. Better replace them with electronic ballasts. The former produce one or two flashes when you turn the tubes on, the latter make the tubes produce at the first shot the light (do the test in the morning when the tube is cold).

If you have an electronic ballast, and you already have a tube 8(35/40/54), then the source of your eyestrain is something else.

Check the monitor, reduce sources of reflections (or of diffused glare if it is a matte display, as it should be, in general, for office work).

Check the distance between eyes and monitor: it should be at arm-length distance.

Take breaks and look around, outside the window, etc, even 10 seconds every 10 minutes help a LOT, use Workrave for Windows or AntiRSI for Mac.


Replacing Light Fixture with Extra White Wire

First never attach unidentified conductors until you identify what it is (standard service electrician training). The lone white conductor that was isolated could very well be a switch leg or a non neutral conductor. It should be identified by a phase tape (black, red or blue tape or some other method), but this isn't always done.

So take the lone white wire off of the neutral, cap it off and leave it alone. Then see if they lighting circuit is working properly and make sure no damage was done by connecting it up. If not knowing what that conductor is for is really bothering you, then trace it out or hire a professional to inspect and identify your circuits and make any corrections as needed.

Good luck and stay safe.


Can I mount 3 blades on a 5 blade ceiling fan?

No, it will not be OK.

A fan blade system is meant to be balanced. Even when all of the original equipment blades are in place, minor imbalances can occur and need to be corrected with weights from a balance kit. Failure to have a balanced fan causes wobble. If the wobble is bad enough, it can damage the motor, loosen the fan in its mounting and even cause mounting failure.

The five existing blades are evenly spaced. You can get replacement blades, but they have to be the same number as the originals. If you mount on only three of the five brackets, two blades will be next to each other and one will be opposite. This is a very significant imbalance and could lead to catastrophe.

If there were a way to mount the blades evenly around the perimeter, it might work, but that would require a whole new and custom crafted bracket system.

SUPPLEMENT: The Questioner has added information, now indicating he intends to mount the blades evenly spaced. If that is achieved, balance should not be an issue. Care must be taken to ensure that the adapter used to mount is also balanced around the perimeter (an added bracket on only one side would still create imbalance).


raising my existing concrete floor 20cm up

No, The existing slab is an excellent base.  Fill it with the least expensive aggregate you can buy and pour your new slab.  Good Luck and happy finishing.


How do I fix gaps around my lean-to greenhouse?

Make a wood frame with the required taper.

This may also help with sealing to the surface of the wall.


What can I do about cracks in a stone foundation?

You need to get a professional home inspector onsite. He should be capable of telling you whether these are cracks of structural significance or not, and discuss remediation measures (not cost thereof).


Mysterious Metal Plate on Basement Ceiling?

This appears that they used the channel between studs as a return air duct.  Look at the duct that attaches to it and see if it is also a return air duct or if it goes to the return side of the air handler.

That said, drilling a small hole to hang something should be fine.  Make sure you drill as close to the center of the stud as you can - you don't want a random hole in the return air duct if you can avoid it.  If you have some kind of hole-drilling accident, a piece of aluminum duct tape or duct sealant should fix it.


Can "bending" screwdrivers really apply enough torque?

I have had one for 45 years and have used it a lot. It was part of a screwdriver/socket set I got from my little sister for Christmas. The screwdriver bits are not as effective because you can't put your weight behind it and the bits have a tendency to turn out of the screw in some cramped places. It works very good with the sockets because the torque is just about as good as a standard nut driver. This is one of those crazy tools you have that you won't use a lot, but when you need it, you'll be glad you have it, like an offset screwdriver or the little stubby screwdriver.


Temporarily using 240v electric hot water heater with 120v from generator

Your math is on the money

You are indeed spot on that your heater will draw 9.375A when connected across a 120V supply.

And your 120V wiring is correct as well

You are indeed correct that the two water heater hots should be connected to hot and neutral of the 120V supply, and the supply ground should ground the water heater.

However, your 240V wiring is a miss

You have the wrong plug and socket configuration for your 240V wiring though.  While it's not unsafe currently if it was wired directly back to the main panel as your appliance is 240V only and thus needs no neutral, the NEMA 10 was intended for 120/240V apps, not 240V-only apps like yours.  The correct plug and socket is a NEMA 6-30, which is "hot-hot-ground" instead of the "hot-hot-neutral" of the NEMA 10 series.

I'd replace the NEMA 10 with a NEMA 6 and then either:

use an adapter cord wired as you describe (with 14AWG wire) to plug the NEMA 6-30 into a 5-15 (regular) receptacle.  Make sure to label the cord as "FOR WATER HEATER ONLY" so someone doesn't use it on an appliance that will pull 30A at 120V -- a 15A/250V fuse in the adapter assembly would be a wise thing to have, even, as protection against such oopses.
change cords when making the generator connection, as your water heater has a terminal box on it that can be used -- a 14AWG power cord with screw leads at one end and a normal 5-15P at the other can be used, wired as you describe.  Make sure to wire up the water heater end first, and not to leave the unused cord connected at either end!

How to hardwire this switcheroo (properly!)

If you want to configure this as a hard-wired sort of thing (for instance, if you already have a transfer switch or generator interlocked subpanel installed), it's not impossible (or particularly expensive), it just requires a bit of unconventional (but still Code insofar that putting a 240V water heater on a 120V supply can be considered Code to begin with) wiring.

You'll need for this:

A Reliance Panel/Link TRB0603D manual transfer switch
Some /2 with ground cable of the appropriate type and a gauge that matches the existing wiring from the generator inlet
An Eaton BRWH220 breaker -- you'll probably need to have your supply house order this in for you, but it shouldn't be terribly expensive
Wire nuts and THHN that match that existing generator cable for a bit of pigtailing
And inch-pound torque tools and bits for assembly

First off, make sure that existing breaker for the water heater is off, and that your water heater is a conventional electric tank heater with an electromechanical thermostat and no existing connection to the mains neutral (putting 120VAC on a heat pump or hybrid water heater will lead to severe compressor damage, while tankless electric heaters are simply too beastly for any reasonably sized residential generator to have a hope).  You'll also need to torque all the lugs you're fitting wires to the manufacturer's specification -- this is a very good reliability measure in addition to being a new requirement (110.14(D)) in the 2017 NEC.

Pick a spot where you can cut the water heater branch circuit and run a cable conveniently to the existing transfer means, then cut into the water heater circuit and install the new transfer switch there.  Land the existing hot wires from the breaker on the lugs of the new transfer switch's "utility" breaker, and land the hot wires going out to the water heater on the main lugs inside the transfer switch (they're the two large lugs attached directly to the busbars).  Land the ground wires on the ground bar.

Now, run that new length of /2 cable from the existing transfer means
 to the new transfer switch.  At the existing transfer means, splice into one hot leg with a THHN pigtail and a wirenut -- the pigtail routes to the terminal the hot leg in question once landed, and the black wire from the new cable goes into this splice as well.  Do likewise with a matching pigtail and the generator's neutral wire, this time hooking the white wire from the new cable into the splice, and land the new ground on a ground bar.  The result is a generator-only 120V feed to the new transfer switch.

Now, install the BRWH220 into the new transfer switch, preferably on the same side as the generator breaker.  This breaker is special in that it has a pair of isolated line lugs instead of taking its line-in from the busbar stabs, thus allowing it to be hooked to a circuit of different characteristics than what the loadcenter it is in is connected to (say one on a separate meter, which is the originally intended application for this oddity of a breaker).  Take one of the outside lugs (either one works, they're both line lugs) and land the black wire from the new cable on it.  The white wire from the new cable goes to one lug on the "generator" breaker already installed into the new transfer switch, and the new cable's ground wire goes into the new transfer switch's grounding bar.  Last but not least, use another piece of that THHN from earlier to connect the inside lug on the same side of the BRWH220 that you already wired to (that's the matching load lug) to the remaining lug on the "generator" breaker in the new transfer switch.

Button everything back up, turn the water heater's breaker back on, and make sure the water heater runs both off mains and off the generator, with correct voltage (240V for utility power, 120V for generator power) at the terminals of the water heater.  Now, when the power goes out, you'll be able to transfer the water heater to generator power and have it run at half-voltage (quarter power) without fussing with cords or the likes.


Best choice for sub-panel and circuits for basement

What kind of closet will this be? Can't put a panel in a clothing closet.

A bathroom needs a 20A because a hair dryer is 13A all by itself nevermind the curling iron or hair straightener often set out to warm up while it's in use. Also whatever else, and lights, fan, heatlamp if that's on the circuit too.

I get your idea that it's YOUR house and YOU can cheap out on the electrical system and use your smarts not to overload it. However a) don't overestimate your sense of load size.  b)  I certainly hope for your resale value that you are not the last human who uses this house.  And c) I fail to see the value of cheaping out on electrical.  Given the astonishingly low cost of the parts, you should be optimizing for performance not economy.  Case in point:

The ampacity of the subpanel

First, separate the supply breaker from the subpanel proper.  You can have a 30A breaker in the main feed a 225A panel (the 30A certainly won't melt the 225A panel!)  The reverse is not true, obviously.    You would go with a higher amp subpanel mainly so you have extra breaker spaces for future expansion, because running out of spaces is a nightmare that is so easily averted right now, when you buy the subpanel, and extra spaces are cheap.  So in your case I'd go for a 30 space for instance.  Finishing with 60% of your spaces unused is a good place to be. It's so easy and cheap to just add circuits if you have the panel space, so things like under-sink water heaters, electric car, welder, become easy decisions.

Beware of double-stuff breakers. Many panels advertise "24-circuit (12-space)" - the 24 circuits relies on double-stuff breakers, which are more expensive.  Those are bad news because increasingly you are required to use exotic breakers like GFCI, AFCI, 2-pole and the like, and those cannot be had in double-stuff.  So you are stuck with the lesser capacity e.g. 12 circuits.   It's cheaper to get the number of spaces you want, so you can use the simplest breakers allowed.

Which panel?  The breakers must match the panel. Eaton CH panel, Eaton CH breakers.  Most manufacturers make several incompatible lines (CH/BR, Homeline/QO, etc.) The ruling factor is the cost of exotic breakers such as GFCI, AFCI, 2-pole GFCI and the like. So you can cross off several models.  Those exotics are being forced down our throat, so get used to them.   I am also not a fan of tenant-grade cheapies (Homeline, BR).  Siemens has a lot of promise: quality panel with sanely priced exotics.

The panel should be fed with a 2-pole breaker in the main panel, unless you are doing something intentionally weird, but then why would you use /3 feeder?  You should know this, by the way.

I'm a little concerned with a knowledge gap here, and encourage you to hit a library for a book on wiring houses, and read it cover to cover. You don't want a knowledge gap. You especially don't want one after the drywall is up but before inspection.  If your skill is lacking, do the works in EMT conduit so it's easy to fix later!

The circuits

Now, you say you want to run /3 cable.  Either you don't know what you're saying, or you intend to double the circuit so you get 2 circuits out of each cable (a multi-wire branch circuit).  That's awesome. (MWBCs not unfamiliarity).

I was a little worried that you were underpowering things like the bathroom and kitchen, but if you intend to supply them with a /3 and MWBC, that means double the circuits, and the cook will thank you. However MWBCs absolutely require a 2-pole breaker, which means you will need 2 breaker spaces for each one.  Like I say, you go through spaces faster than you expect!

Honestly MWBCs are falling out of style because so many circuits require GFCI or AFCI.  And that requires either the uber-exotic 2-pole GFCI/AFCI breakers, or correct branching at the destination and then GFCI or AFCI deadfaces or receptacles.  And the savings is pretty small compared to running 2 separate /2 cable runs and avoiding MWBCs altogether.

The bathroom(s) require following one of two strategies:

Each bathroom gets a dedicated 20A circuit for ONLY loads in that bathroom, including wired loads like lights, fan, etc.  I am not a fan of this one, because BOOM you are now in pitch black, holding a red hot hair straightener 1/4 inch from your ear, and can't even set it down because you can't see to not set it in the sink full of water. (however if the hardwired loads together exceed 50% of circuit capacity, looking at you fan-heater, that circuit cannot serve any receptacles at all, and this method doesn't work.)
A dedicated 20A circuit serves only receptacle loads in any number of bathrooms.   The hardwired loads are served potentially from other circuits that serve other rooms.

There is one circuit that you really will want to be 100% dedicated, and that is the refrigerator.  Code requires a GFCI since it's in the kitchen, even though that's not really the use-case GFCIs were intended for.  And you really don't want any other appliance tripping the fridge and ruining your food.  For this reason GFCIs on fridges are a terrible idea. I say install a dedicated circuit with a single (not the usual duplex) receptacle, so only the fridge can possibly be plugged in.  Use a GFCI breaker, and I would certainly never tell you to switch it to a plain breaker 5 minutes after the inspector walks out the door.


Attach receptacle box to baseboard via screws through plaster ears?

The holes in the plaster ears of the box will take screws very well. That is what usually holds the box in place when it is mounted in a cabinet.

To allow the cover plate to set well, you could use 4 gauge screws or a larger diameter and countersink the holes in the mounting ears a bit to help let the receptacle set tight to the face of the box. You would do well to break off the ears on the receptacle at the score lines to help clear the screw heads too.


Is the 60T blade that came with my Dewalt DWS780 miter good for general purpose cutting?

A 60 tooth is a fine blade for semi-smooth finish cuts. Cuts on flooring are always at the wall ends, so even a 40 is good for that since the baseboard trim goes over the cut. You should be leaving a 1/4 inch expansion gap at he ends anyway, so they won't show. The DeWalt 12" blade is a good long lasting blade. It has good balance, heat dissipation and takes a beating.  I have several Dewalts and some other much more expensive blades for my 12' DeWalt double bevel chop saw. For most applications, the DeWalt is perfectly fine. If you start doing precision cuts in $6.00/foot hardwood cabinet crowns, then buy a $100 to $200 blade. Judging from your question, you are not to that level, so the DeWalt is a fine choice.


Liquid in Clothes Washing Machine for balance?

The washers are shipped with water in them. The reason is that, at the factory, they have to test them before shipping. Which means you hook them up and turn them on. Washing machines don't drain 100% of the water from the drum, so what you're hearing is the remainder of that test. In most cases, it's probably 1-2 gallons.

The water doesn't hurt the machine(it's designed to hold this residual water, after all). As to freezing, if the water was frozen the liquid water it would add to start a new wash cycle would likely melt it enough to not harm the machine.

A Sears salesman confirmed this on their site

  All washers are tested for leaks with water. It's not uncommon to find a slightly wet spot on the box. The spin basket also has a balance ring attached at the top which is half filled with water that you may be hearing sloshing around. This is normal and the balance ring is sealed to prevent the water from escaping. The balance ring is not likely leaking and the wet spot is likely from when the washer was tested.


Calculating the density of the cardboard seems like extreme overkill here.

Just take a representative piece of your cardboard to the local postal service retailer (like a FedEx or UPS store) or even to a government post office and ask them to weigh it with their sensitive scale. If they ask why just tell them you may need to know for future shipping purposes.


Trying to find 5.5" surface mount doorbell button

Remove the unit and look for manufacturer's marks on the back side. That would be the only chance to finde an exact replacement.

I would probably buy a cheap doorbell button unit and remove the switch assembly for use in your nice housing. You may need to improvise or alter a bit to make it work.


What size power supply do I need to connect two 5 meter LED strips?

It says 2.1 amps/5 meters for the 30 LED/meter strip, 4.2 amps/5 meters for the 60 LED/meter strip. So, that's either a 5 amp @ 12V supply or a 10 amp @ 12V supply.

I would not recommend hooking up the two strips in serial; the LEDs at the end of the second strip will likely be much dimmer than the ones at the beginning. You can get around this by running a thicker cable in parallel with the strip.


Congratulations. You have a bunch of 18-24" chunks of 3/4" conduit. You do not have 10 foot chunks of conduit. Unless you have mechanical plans (I've seen folks do small greenhouses with conduit) might as well cut them at the holes.


ledger boards (is that the right word?)

That is the correct word

  Is 2x8 enough for this or should I use 2x10

2x8 @ 16" oc in the long direction of 14' will support more than 40 psf loading

  Which way should the joists go? (across the short or the long dimension)

The short direction is typical as it allows for higher loading for a given joist size or conversely a smaller joist for a given load. Blocking at mid-span of the joist is necessary. In your case, to avoid a beam, which would likely be deeper than the joists and undesirable in this case, I suggest spanning the longer direction.


Two Electric Ranges with the Same Issues

Electric coil elements with "hot spots" are failing and should be replaced with new ones, not a different range with old ones (possibly the same old ones, if they swapped parts from one to the other, as they are pretty interchangeable and your landlord reads as "cheap".) When they fail all the way, the arc can blow a hole in the bottom of a pot...just not a fun thing to let happen, particularly for a part that's typically $10-$12 or so.
An "unpredictable" oven is vague as heck, but typically you need an oven thermometer to hit temperatures reliably on any oven you don't already know the mapping of "dial to reality" for, as they are rarely accurate. I've had an oven element blow once, which was quite the show, since it arced wonderfully without exceeding the amperage of the range breaker, so it just kept arcing. I was happy that I was in the the kitchen and heard, then saw, it so I could shut it down. It was not subtle.
The range outlet hanging from the wall (or the power supply in general) would not affect either of these, but does reinforce the "cheap or outright slumlord" impression you're giving of your landlord. Often the only real solution to that is finding a new place to rent, though sometimes you can get a tenants rights organization to help you in attempting to fight with them, but it's often a losing (or pyrrhic) battle.


Can I replace upgrade main breaker without changing wiring? (within panel limit)

It it unlikely that you would be able to put in a 63A breaker. The available size would be more likely be a 60A breaker. You also need to consider what feeds this panel and what size wire brings power to this panel.

1) If the panel is feed from the utility company via a power meter then the MAIN breaker would want to be sized according to the wire gauge from the meter and within the ratings of your panel. This would require consultation with the utility to determine what the delivery capability is in Amps.

2) If this is actually a sub-panel that is fed from a main breaker panel elsewhere on the property then there should be a source circuit breaker in that panel that protects the feed wires to the sub-panel. There would be no point to install a larger ampacity breaker in the sub-panel than what is in the main panel. If that main panel breaker is 30A for example and the connecting wiring is 10AWG then it would not be safe to update any part of the sub-panel power delivery to higher capacity without upgrading the wiring to a proper increased size and possibly changing the feed breaker in the main panel to a size that is compatible with the wiring installed.


How can I remove rust from a washing machine cabinet and protect against future corrosion?

Since no one has addressed the real problem here, recurring rust, I will. Your rust keeps coming back because it is rusting from the inside out, plain and simple. It may not seem like it at first, but from my experience, if and when you clean rust and seal the surface, but the rust keeps coming back, that's because it's rusting from the inside out. You need to inspect the inside of your machine and its internal structure and look for any internal leaks. Once you identify the internal problem and resolve it, then you can again clean the rust and seal the surface because there is no internal rust that will come through again.
I hope this helps.


How to repair the leg of a computer chair

Replacing is probably most practical.

But if you really want to fix it, you need something to support the weight.  Tape and glue aren't going to do it. I would find a length of strong pipe (check the plumbing section at a home improvement store) that will fit nicely either inside the leg (if it is hollow) or over top of it.  Make the pipe fill/cover as much of the leg as possible.  Then attach with tape, glue, bolts, whatever - just to stop it from sliding out.

If the pipe fits snugly it should hold up fairly well.


What is the proper, safe, and effective way to apply diatomaceous earth?

We have used DE effectively to kill bedbugs, so I'll take a shot

  how should it be applied?

We applied it around the borders of all the floors, sprayed it into the walls everywhere we could (mainly into electrical boxes - remove the covers first), and into the underside of plush furniture.  In the basement we put it all over the ceiling and walls as well as squirting it into every gap we could find.

  is it effective against bed bugs? How long does it take to kill them?

Yes.  They will avoid it if possible, so its tough to say how long it takes to kill them, but when we applied it to a heavily infested house and the improvement was immediate.

  where should it be put? Everywhere, or only in specific locations?

Anywhere bedbugs can get.

  how much should be applied?

A dusting around the perimeter of each room, a generous squirt of dust into openings and several squirts into plush furniture is what we did.

  how often does it have to be reapplied, and does it have to be vacuumed up?

We only applied it once and that did the trick.  If you vacuum it up it can't help, so no don't vacuum it up.

  after it's been applied, will a fan or wind disturb it and blow it into the air?

Depends on the orientation and strength of the fan.  A ceiling fan? No.  A box fan pointing at a line of DE?  Probably.

  is it safe to apply it on a bed?

You should seal your mattresses up with bedbug preventing covers, and squirt the DE inside that.  DE is harmless to you, but you want to trap the bugs in the mattress.  Leave the mattresses sealed for at least 2 weeks or longer to ensure the bedbugs get exposed.  They can hide and live for a long time in a mattress but a solid month should deal with the birth cycle.

  is it effective when wet? when the air is humid?

No and not very.


Barrier around shed base to hold dirt for retaining wall?

You want air flow under the shed to keep it dry. The traditional barrier around houses on piers was a wood lattice, mostly aesthetic, and of course unwanted critters would get past it.

I don't understand your idea of a retaining wall and a barrier with a 2 ft gap. The purpose of this is not apparent to me; it sounds elaborate and a lot of trouble. My initial reaction is that Tyvek wrapped around wood in contact with soil would not protect the wood from rot.

Plants around a shed are going to lead to watering around the shed. I can see that just a lattice around the perimeter might seem stark, but there is a reason this was traditional. Whatever you do, leave some convenient access to put rat traps under the shed. If and when they are needed, put them in the special boxes to prevent pets or any non-target animals from being trapped.


Finding replacement for antediluvian lock


Why are "horseshoe" shims shaped the way they are?

I used these extensively in my kitchen remodel. Wood shims always seem to split on me. And, since I live in a humid area, wood shims disintegrate over time. Many of my original base cabinets have settled leaving a gap between the counter and the backsplash.

This is how I assumed that they should be used. When hanging wall cabinets, you loosely tape them to the wall (open side down) where you think that the screw will be installed. The screw goes inside the horseshoe, near the top. The shim is now captive, the pressure should hold it, but if it doesn't the screw won't let it fall out.

Why not round? Probably so you can insert them after the screw if necessary.

The horseshoe shims that I used were slightly different, they had flexible tabs so they could be stacked.


Should I use a hose clamp on my furnace drainage pipe?

It is proper to put a hose clamp on a connection like that as often the barbs aren't sufficient especially after it's come off a few times.  If you're worried about damaging the fitting from the furnace just add another fitting after it and secure it the the furnace or floor, etc.  Then your standalone fitting will be the one that gets damaged if somebody kicks it hard.


Is it important to finish rafter tails, (sub)fascia, and barge rafters?

Yes, you should finish all exterior wood no matter whether it will get rained on or not as wood still can rot simply from ambient moisture in the air.


Cannot get to the screw behind disconnect switch

Think the screw has nothing to do with removing the dead front. Think this is how:
Turn the switch to OFF.
Lift up the top plastic section using the holes on the side. This will allow lifting or prying the bottom section over the stop on the bottom.
But it may be that you just pry on the bottom in the central slot.


What are the pros and cons of prefab granite vs. custom slab?

The big difference as you mentioned is price.  The seams with the pre-cut pieces should not be an issue (assuming the installers are good at what they do), the more noticeable factor will be the difference in colors and patterns.

If the entire counter is cut from a large slab, the colors and patterns will be consistent throughout the entire counter.  If the counter is assembled with pre-cut pieces, you may notice differences in colors and patterns from one piece to another.  The choice here, however, would come down to preference.  Some people might prefer the look of one method over the other, so it's hard to say what you'll like better.

I would find out if they have a show room or can provide pictures (from previous jobs) of the different methods, then you can decide which you personally prefer (while keeping your budget in mind).


I pulled out the box out with the white sticker on it by gently pulling both red wires and it revealed the white, black and ground I was looking for.


What does "8(3)A" mean on a relay spec sheet?

I can't be 100% without a relay part number or datasheet -- but most commonly, that type of specification would be 8A switching a resistive load (say a small heating element), and 3A switching an inductive load (say a fan motor).

Solid-state inputs and relay coils generally don't draw enough current to be a problem.


PEX vs PE coiled pipe for underground use

"Black polyethylene" seems to commonly refer to HDPE pipe, which is pretty comparable to PEX.  "Just" PE pipe is cheaper and less durable than HDPE - I'd advise against that underground.

PEXa ("Uponor/Wirsbo", "ProPEX", "F1960") is the best option, especially underground and in places with a potential for freezing, since it simply expands and contracts instead of bursting and leaking.  However, PEXa is a bit more expensive and requires "expansion" style fittings, which while they are most reliable and free-flowing of all PEX connections, typically require more expensive tools that may not be worth it for a one time job if you can't rent them.

PEXc is the more common and typically cheapest form; connections are commonly "crimp" or "clamp" style which are more restrictive than expansion style, but the tool tends to be cheaper.  PEXc will also expand and contract, but to a far lesser degree before risk of splitting.

Ultimately, PEX is the best option these days, but the type of PEX is more dependent on your situation.

If you plan to do more plumbing in the future and/or the pipe could be subject to freezing, PEXa along with Milwaukee's expansion tool (Milwaukee #2432) is the way to go for worry-free connections.  There are also hand tools available for about half the price of a used Milwaukee kit ($160-200 on eBay at the time of writing).
If you can't rent or find the expansion tool for a reasonable price, or are simply more budget minded, PEXc using crimp or clamp style connections is likely the best path.  Home Depot near me rents the tool for $16/day.


How can I repair small holes in vinyl siding?

If your vinyl siding has a color to it, there are one part polyurethane caulks available like Sikaflex that can be ordered online that should match your color, at least a close match so it does not stick out too bad. If the siding is white, well, that is available right off the shelf. Clean up is with mineral spirits and it will last a real long time. It does not have to be Sikaflex either, there are other brands of one part urethane caulk out there too.


What can I use to determine the proper size of faucet aerator to buy to replace the existing ones in my american standard faucet?

Any sizing chart online won't be accurate because the sizes are so close together. Your best bet is to take your old aerator to a home store. They usually have a template gauge you can screw your aerator into to determine the correct replacement size. Taking it to a plumbing supply store would also work. They could tell just by looking at it.


Problems with GFCI outlets recently installed

Some insight and advice: hire an electrician for this.  If you'd done that in the beginning you wouldn't be here asking for insight and advice.


Are gutters the only way to fix this ice accumulation issue?

Sure, there's a solution that requires no annual maintenance (well, no more than the whole house needs) but that would be to rebuild the roof so it does not dump there. Which you might consider a rather major task, but hey, you asked. Thank the architect for causing the problem for you.

Simplest solution will be a section of gutter and a section of heating cable (run only as needed) to keep the downspout and gutter functional with ice. But you might need to clean it, yes.

Most absurdly expensive solution to operate would be to retrofit ice-melting heat (electric cable or fluid/heat exchanger) into the walkway itself. Truly crazy expensive to run, but some places do that.


How can I tape drywall joints at the ceiling with existing texture?

Or you can caulk the joints and smooth it out. Use a caulk you can paint over when dry.


Yep, you need to worry about the structure. You may be fine with a pressure treated box-frame inside the void, if the section isn't directly load-bearing.

But typically, a proper steel angle lintel is required and that must run at least over half of the neighbor block width. A call to a Mason might surprise you with how cheap it'll be for them to knock it out.


Can I use a transformer to run a 120V/60Hz appliance on a 220V/50Hz electrical system?

Yes, you could buy and install a step-down transformer.  However, heating appliances use a lot of power (an electric grill might use 900–1500 watts) and the corresponding transformer will likely be as much as the price of the appliance.  Here are some which might do.  Notice that a 1500 watt transformer weighs 18 pounds (8 kg)!  The transformer should be rated at least twice the nominal load of the heating device to handle the cold start power curve.

If you are in an area with unstable voltage, a regulated transformer would provide some protection against under and over voltage.  See these.

It is certainly better to buy an appliance which adapts to different voltages—which is easy with most electronic gizmos like computers and cell phone chargers—or is made specifically for 240 V.


I need to know what is the name of this valve that is for my outdoor water line and where can I get a replacement?

It probably does not matter what type valve it is. Looking at the part you show, I do not thing that you will be able to repair the existing valve, or be able to find parts to do a repair. I would replace the valve with a name brand, top quality, American made valve. You could use a gate, globe, or a full port ball valve. The part you show looks to be from a rising stem gate valve, but I could be wrong. I would have to see the whole valve to be sure.


2 hot wires into light switch and no neutral

Belatedly -- from the OP's description, it appears that the original wiring was quite naughty and used the metal conduit as a neutral.  This'd explain the lack of a return current path once the conduit was cut back to repair the wiring insulation, which is also a no-no as you probably won't get it back together again without an excessive amount of work.

Not only does the OP need an electrician, the OP needs to warn their electrician about this lest they zap themselves unwittingly!  (A family friend of mine who is an electrician encountered a similar issue, only finding out when a conduit fitting arced as he went to repair it.)


Refrigerator intermittently making loud clicks with compressor banging and shaking

That loud click is probably an overloaded compressor relay. When compressor components start going bad it can cause all kinds of issues. You can do some reasonably priced troubleshooting by installing a Hard-Start Kit. Here is a link to a video that shows in more detail how to install it.


This is something that needs a structural engineer. If you want to try to do your own calculations, here is how you do it. First you start with what a beam can hold at all.
https://en.wikibooks.org/wiki/Strength_of_Materials/Loading_of_Beams

Then you move to what dimensional lumber is capable of:

https://awc.org/codes-standards/spantables/tutorial

But to calculate what sistering would do for you is actually not that simple in that ostensibly if you have two 2x12s sistered, it should be the same as a 4x12. But in reality if they are finished dimensional lumber, the 2" is actually 1-12", so two of them sistered is 3", vs a 4" dimensional beam would be 3-1/2" wide. Then you are complicating it further by staggering sistered beams to try to get a longer span. I'm not saying it can't be done, but this site is not the place for it, you need an experienced a pro to do that.


Vinyl flooring poor air quality and toxicity

Most building materials will off-gas for for various reasons: 1) what their made of, 2) what they use to “glue” material in place, 3) warring of surface material. A better explanation is here:

https://www.greenbuildingsupply.com/Learning-Center/Flooring-LC/Why-we-dont-sell-luxury-vinyl-tile

What this article omits is the adhesive used to secure the material to the floor.

Even “low VOC” material has a significant amount of material that will “off-gas”.

Government buildings now require the completed building to “run” the heating and air conditioning systems without anyone in the building for 14 days. We usually don’t do this for residential construction because there are larger quantities in governmental buildings.

Everyone has a different tolerance towards these materials. Not much can affect me, but my son would cough and gag after a few minutes when we stayed in a hotel on vacation that recently renovated their rooms. Your tolerance may be just as weak.


How can I add support for my floor inside a rigid metal return vent?

One option to consider would be a set of pillars under each individual floor board, wedged or glued firmly in place, perhaps only secured on the bottom to allow for thermal movement.

This concept extended within my grey matter to suggest a plank running across all the floor boards, but with holes across the span to provide for the airflow.

The pillars could be hardwood dowels of an inch diameter or larger, or strips of lumber with the grain oriented for maximum support.

A plank with holes would be more restrictive, but having more than one option isn't a bad idea.


What kind of thinset should I use on porcelain?

If the tile maker does not have a suggestion (they often do - see if they have a website if there's nothing in or on the package) any thinset and a notched trowel somewhere between 1/8x1/8x1/8 and 1/4x1/4x1/4 (depending on floor flatness) should do. Concrete is an excellent tile substrate (does not tend to move or flex) so there's no need for special acrylic modified flexible thinset.


Need More Water in Quikrete than Recommended

You should mix according to how you want the concrete to flow. Watering the forms and the ground before you pour is important when the climate is dry and hot. You are correct that the water mix affects the strength of the final product, but not as much as you may think. The most important factor is how much Portland is in the mix, and second, how fast it cures. Make sure that you pour when it is not hot and sunny, like in the evening or shade. Cover the work to prevent drying out, in fact, it needs to keep wet for a few days, so sprinkle water on the surface until the product turns white. That may take a week. The closer you adhere to keeping it hydrated, the better your surface will hold up over time.


Use enamel. Latex is too soft for book shelves. Using the right primer is also important and this depends on the material you are trying to paint. You don't want the paint to be removed by placing things on the shelves, so the bond to the base material needs to be strong. I don't think the primer you pictured is an appropriate primer for the job. The primer needs to be as hard as the topcoat or you get cracking in the topcoat. It's a little funny that the Rustoleum website has a video of someone painting a book shelf using that primer. I can't tell you the number of times that I've seen things stuck to shelves because the wrong paint was used. That primer even states that it's flexible... AKA too soft for book shelves.


How to bypass the ballast on this fluorescent fixture?

That style has electronic ballasts (as opposed to magnetic) integrated into the fixture ends and will not be easily converted (if it can be converted at all).

They are very inexpensive low-end type fixtures and are meant to be thrown away rather than repaired when something goes wrong. IMO that fixture is not worth converting, just get a whole new modern LED fixture.


When you

  disconnected all of the neutral wires.

You changed the configuration of the circuit. Basically all circuits in the US are wired in parallel. When you disconnected the neutrals you change that circuit into a series or combination series/parallel circuit. The only thing you are reading by testing the hot circuit against the two disconnected neutrals you show in you drawing, is whether or not it is an open circuit or there is still a connected load on the circuit. So if you are reading 60V it could be a phantom voltage or it could be the the series reading of the drop across you meter. That means if you touch it you will find out why we call it a series neutral since it will shock you.

You question isn't clear about what you were testing the circuit for other than you stated you were testing for voltage drop. If you are trying to test for voltage drop then you are doing it all wrong. Voltage drop is directly proportional to the load of a circuit. That means you have to have a load in the  circuit to determine your voltage drop.

Let's say you have a motor at the end of your circuit. In order to find the true voltage drop for the motor, it should be running at full load. Then you would take the measure the voltage at the breaker to the neutral (let's say it's 126V) then take another reading at the motor connection point (say it's at 122V). Then you know you have a drop of 4V between the breaker and the load.

Because you are exposing yourself to live electricity, it is difficult to measure equipment while it is running. In order to determine voltage drop in most cases we perform a voltage drop calculation.

Point being when you disconnect all of the neutrals, you will get all kinds of strange readings that really don't mean anything relevant to the complete, operating electrical circuit.

Hope this helps.


Stairwell ceiling fan direction for non-heated or cooled entryway

The general idea is
Air blowing down = cool
Largely this is a felt effect, because the air is moving over you, i.e. wind chill

Wind Chill is a term used to describe what the air temperature feels like to the human skin due to the combination of cold temperatures and winds blowing on exposed skin. In simple terms, the colder the air temperature and the higher the wind speeds the colder it will feel on your skin if you're outside. So even if it remains the same temperature, but the wind speed increases it will actually feel colder to your skin.

Air blowing up = warm
Hot air rises. Pulling colder air up and out pushes it off the ceiling and towards the walls and down. Because you don't feel the effects of the air movement directly it doesn't add to the chill effect. This one has less noticeable effect because it's trying to mix the air. It's also greatly influenced by how much insulation your ceiling has (less insulation = less heat for the fan to push). Still, it's better than nothing if you're looking to milk efficiency. It's also less effective in larger rooms, where the walls are not close enough to help force the hot air down.


kitchen backsplash tile grout or caulking

You might push soap or grime into the gap at the bottom of the cabinets when cleaning the tiles, so it's probably a good idea to seal the gap. I didn't do this in my kitchen and I think intelligent life is evolving in there.

I'd use silicone caulking instead of grout at the these locations, because it's more flexible, and I'm convinced that there is always some tiny flexing or movement between the cabinet or the counter top and the wall.


Put a junction box inside the basement (i.e., right at the point where the wires exit to go outside). Romex on the inside (to make it easy to run it through the basement) and conduit on the outside (including through the wall and all the way down & around to the subpanel) with THWN. One extra box and you get the best of everything. The box does need to be accessible - can be high up on a wall or behind "stuff" but not hidden inside a wall or ceiling.


Why would a single receptacle fail after updating other wiring?

The short version of the solution is: when you see a very old junction that is taped together, unwrap it completely (while the circuit is off), and inspect the junction directly. Then, fix as needed, and replace the tape with wire nuts. The new upstream wiring had nothing to do with the actual problem, and the wiring inside the old downstream junction box must have shaken loose during demolition. Troubleshooting it the first time resulted in the accidental rejoining of the wires within the box, restoring continuity, and creating the illusion that the outlet was the problem. The first repair worked out on a fluke.

How I missed It: The issue was not with the outlet, but inside a junction box that was ruled out since it was not accessed until the problem with the receptacle arose. While the circuit was off, I removed the old receptacle and opened up the junction boxes between it and the panel. After restoring power to the circuit, testing the bare wire immediately yielded ~126v. So I shut it back off, installed a new outlet, closed the boxes and restored power. Done deal.

Three days later, no power again. Actually, very low power. After the second time the outlet stopped delivering proper voltage, I decided to diagnose the original receptacle before removing the new one. It was fine.

Checking for continuity and shorts with a meter: Disconnect and remove the outlet. Set your meter to resistance/ohms. This is a little more reliable than continuity (if you have that), because you can have a resistive short that may not register as full continuity.

Test the receptacle in groups:

Neutral Group = long slots & silver screws
Hot Group = short slots & brass screws
Ground Group = round holes & (usually) green screw on the mounting frame

Touching the probes to any two points within a group should read zero or nearly zero ohms. High readings or no response indicate a dirty, loose, or broken internal connection. Any points from two different groups should yield no response from your meter. If you get any reading, there is a short.

Finding nothing wrong with the original receptacle brought me to the realization that something else happened with the wiring. I removed the new one to confirm that the bare wires still read low. Working backward, the junction nearest to the the receptacle has an old porcelain light/power socket combo. Testing that power socket also yielded full power, so the problem was absolutely with the one cable between that box and the actual receptacle. Opening that box up immediately gave me a reading at the trouble spot. It became obvious that the issue was a loose hot connection in an old junction box hidden by tape.

One final tip... Testing a receptacle/wiring on a confirmed working circuit that is on. If you get a reading on your hot (black) to ground (bare), but nothing on your hot to neutral (white), then your neutral leg is open. If you get no reading from hot to either one, you most likely have a break in your hot leg. If you get a reading on hot to neutral, but not hot to ground, you have an open ground. In my case, I got about 36v to neutral, and 40v to ground. Ruling out the outlet, and getting nearly the same result on both made it rather obvious that a hot wire was loose somewhere.


How to find out what breakers are compatible with my panel?

Match the letters

If the breaker has the same "Type" letter markings on it as are listed on the panelboard label, you're fine.  Number suffixes on the type marking (such as QAF2 vs QAF and MP-AT2 vs MP-AT) are used to denote a revised type of breaker that is still compatible with the original and can be used in place of it, so they don't matter in your case.

10kAIC is fine

The Siemens/Murray line of breakers comes in three interrupting rating options -- 10kAIC, 22kAIC, and 65kAIC.  The larger options are more costly due to extra internal equipment needed to break bigger arcs, and are only necessary in commercial work where larger services and feeders capable of higher fault currents are found.

In addition, in a main breaker panelboard such as yours, a breaker with a lower rating can be used because it receives a higher series rating by way of being "backed up" by the panelboard's heftier main breaker.


Will I have trouble running a bathroom fan 10 CFM (25%) stronger than needed?

An extra 10 CFM won't hurt you at all.... If anything, it will get rid of the unwanted moisture faster. I'd wager that article was meant for much larger bathroom fans.


Can I put small nails through plexiglass?

Fine nails are fine. But you do need to drill a clearance hole the full diameter of the nail shaft through the plastic. You may want to drill a smaller pilot hole at least partway into the wood to reduce the chance of splitting.

Any standard drill bit will do, but go very slowly to avoid melting the plastic as you drill.

Drill bits tend to walk on plastic, so you may want to put a piece of masking tape over each area to be drilled, which will give a bit of grip to avoid the slide.

Screws would also be fine (and a bit stronger; maybe overkill), but the same pilot hole rules apply.


Damage when drilling a mirror — normal or not?

Is my cabinet maker correct

They are right that drilling clean holes in glass is more difficult than in wood or steel.

In my opinion, they are not right to say that visible cracking around the hole is normal.

They are a professional and part of the price they charge is for having the skill, experience and tools to do the job better and quicker than you can. The hole on the right suggests they can get an acceptable result at least 50% of the time. In my opinion, they should have factored into their price the cost of wastage in redoing work where needed.

  should I ask for a new mirror?

That's up to you. If you are going to stare unhappily at that defect every time you use that cabinet then you should get it fixed now.

How you do this is a matter of negotiation - because you probably don't have a written contract that specifies explicitly what constitutes an acceptable hole in the mirror.


no more oil in cub cadet self propelled lawn mower

I doubt that your real problem is burnt oil sitting in the engine - the most likely way for oil to be burnt and causing smoke in the exhaust is if the rings are bad and/or the cylinder is scored (possibly because of running too long without enough oil).

You can get a good sense of whether your engine is burning oil by checking the spark plug and looking for deposits or other fouling.

If you're really worried about the oil (i.e. if it's extremely dirty or diluted), change the oil (don't just top it off), then run the engine  long enough to warm it up, then change it again.

If the engine doesn't run well with new oil, an engine overhaul is probably your best bet (and usually not that hard to do with a single cylinder small engine if you can find an overhaul kit for it). If the cylinder is scored you might be able to have it bored if you can find an oversize piston and/or rings.


What is a good way to humidify a (temporarily) vacant desert home?

I suppose if you want to pay for the electricity to run your furnace, A/C and humidifier all summer while you are not there, that is certainly an option. But if you consider that all these parts have a service life, do you really want to spend 50% of that service life running them when you are not home?  There's also the problem of if it breaks or otherwise stops running, how will you know?  And of course, your A/C will be working to dehumidify the environment which might be the opposite of what you are looking to accomplish.

My in-laws have a place in the desert with lots of wood furniture and they always just leave buckets of water out and so far have not had any issues with cracked wood.  It sounds like this is a cheap and reliable method.  Perhaps you could find someone who can check in on your house after a few months and fill up the bucketes if needed.


Two by tens are insufficient, and will sag over time. I would suggest a lam beam for this.


What size uncaulked gap should be left at the bottom of a shower tile job, to allow draining?

Fire your contractor. The tiles aren't set square, the grout lines look HUGE, and the grout is discolored.
Caulk the entire perimeter. You might allow a 1 inch horizontal gap on each side for a weep hole as suggested by @freshop.


Oven won't light unless it's hot -- but it can clean!

As others have suggested, the first thing to check is that all your valves are fully open.

However, since you don't seem to be having trouble getting up to temperature, it seems less like a supply or regulator problem and more likely to be about location of the pilot / ignition source.  Either it's not clean, or position relative to the gas is off (could be not enough gas, or not enough supply air).  Make sure your stove is level. If that doesn't help, see if you can clean/replace or adjust it.

A good generic step by step troubleshooting guide can be found here, which lists the order of trouble shooting for a milivolt ignition (the kind of pilot you hear clicks) with as:

The gas valve
The thermostat
Cleaning the pilot orifice and pilot generator
Adjusting the pilot generator height
Replacing the pilot generator and safety valve


Is it possible to install a ceiling fan without an electrical box?

Based on your description, I "see" the ceiling cut out, a resin disc screwed to the joist. The disc has two or more empty holes that correspond to the device mounting holes in a standard octagonal junction box. Then there's a length of romex cable just hanging loose to which you're supposed to connect the fan.

If your fan's installation instructions indicate some part of the fan can be used to make connections, such as the ceiling canopy, you may be in luck. Make the connections there. More than likely, they'll assume you are providing a junction box in the ceiling. First ensure the fan's mounting kit is compatible with your resin plate. You'll need to get the wires from the down pipe, through the plate and into a nearby junction box you will install. The fan wires need to be long enough that there's at least 6 extra inches after running into the box. They must not bind against anything.

You'll need an old work box, a blank cover plate, some wire nuts (may be part of the fan kit), a short length of 1/2" flex conduit, a flex to box connector, and a plastic conduit bushing to protect the wire insulation where it goes into the conduit above the fan. You'll also need a romex to box connector if the box does not have them built in. Any wire running in a concealed structural space needs to be in conduit or non-metallic cable (romex), or a few other less common options.

You install an old work box by cutting the proper sized and shaped hole in the ceiling in a place where the box will not hit anything above the ceiling but is close to the resin plate on which the fan will be mounted. Do not install the box at this time, I'm explaining what will happen, but there's other things to do first. You would place the box in the hole, the box's flange keeps it from being pushed through. A couple retaining tabs are turned with a screwdriver so that the box will no longer be able to be pulled out.

If the romex cable is not attached nearby to a joist, you'll need to do so through the box hole. Locate the hole so it's close enough to do this, but not so close the wire is kinked or crimped after the box is installed. Remove an appropriate knock out in the box to connect the conduit. You can cut or drill a hole if need be. After securing the romex, feed it into the box. Feed the attached conduit through the hole and back out through the resin plate. It can be routed next to the plate as long as the fan ceiling canopy fitting will cover it. Or cut a hole in the plate if need be. Install the box and cut the conduit to length at the resin plate. Install the protective bushing. Install the fan on the resin plate. Push the fan wires through the conduit at the resin plate and into the box and make the connections. Install the fan ceiling canopy and box cover plate.


How should I refinish a pine shelf unit?

Plaster/mud is not meant for wood, it's meant for plaster/drywall, so you definitely should use wood filler.


What is this orange yellow substance on my wooden studs inside walls?

You are looking at tree sap. It's harmless. It's dried out so if it's gonna cause you to lose sleep at night, just scrape it off with a chisel.


If this were a commercial installation you'd need to provision 180VA per yoke, or ten duplex receptacles per 1800W (15A) circuit.  However in residential, there is no limit.

However that won't help.  Essentially what you're saying is you want your outlets divided into enough circuits that you never get an overload trip.  That's a tall order.  You're talking one circuit per receptacle.  I'm willing to do that in a kitchen or bathroom, but all over the house? This rapidly reaches a point of diminishing returns, and it doesn't solve the underlying problem.

Understanding how to use electricity

It wouldn't matter if you had 2000 receptacles on a circuit.  Whether it blows or not depends on what loads are in use, what current each load individually draws, and what the total current is. 3 cell phone chargers, 9 LED lights and a table saw, that'll be fine.  A table saw and a dust collector, not gonna happen.

Overload trip

There are two possibilities here.  One is that your pressure washer, combined with the other loads on that circuit, is drawing more than 15 amps.  You will have to research that yourself, but the general concept is that you should learn what each of your loads draws.  It has a nameplate which states rated current, or you can get a gadget called a "Kill-a-Watt" which will tell you what it actually draws real-time.

GFCI trip

The other possibility is that the appliance has a ground fault.  This is, after all, an appliance that involves water.   Somewhere you have a GFCI device which will tell you.  There is a fair chance it is not at the outdoor socket location, as putting GFCI device outdoors tends to be really hard on them, and they can protect the entire circuit from elsewhere.  Anyway, if it is a device that ONLY does GFCI - a GFCI receptacle, switch or deadfront - then you know it was a GFCI trip.  However if it was a GFCI breaker, you need to get its documentation and follow its procedure for determining whether the trip was a ground fault or overload trip.  Most of them make it rather easy.

If it indicates a GFCI trip, move the appliance onto a different GFCI circuit, such as the bathroom or kitchen.  If you don't want to operate the appliance there, get a 3-prong extension cord plugged in there.


Can a problem with heater stack liner cause outside chimney mortar to crack and fall out

Rain a day after pointing work will help, not harm, the cure. Freezing weather would harm the cure.

High efficiency furnaces output low-temperature flue gas - more heat in your house, less up the chimney = higher efficiency.

Flue gas is always moisture-laden, and starting at a low temperature and then dumping into a cold masonry chimney means the moisture will condense out inside the chimney, rather than exiting as a gas and condensing outside the chimney. Depending on the gas quality, this condensate may be somewhat acidic, thus corrosive (attacks mortar, steel etc.)

It would be worth checking your furnace manual for chimney recommendations - many of the very high efficiency units actually want to be vented into PVC that's sloped to let the moisture drain out (or at least has a drain at the bottom, if vertical.) The temperature (on those furnaces) is so low that PVC is perfectly adequate for the temperature, and it has good chemical resistance. A stainless steel liner would be another possible option - a masonry liner might well not. In any case, what you use should comply with what the new furnace wants, which may not be what the old furnace had (or needed.)


It's effectively a SE Style U cable, even though they didn't call it that back in the day...

From the information and photo given, we can tell that this is a Type SE (Service Entrance) cable with two type RH insulated 6AWG aluminum conductors, a 6AWG concentric bare neutral or grounding conductor, and a cloth jacket.  Modern cables with this construction would be marked as Style U for an Unarmored type of cable (vs. Style R for a tape Reinforced cable construction, often with four wires instead of three), but your cable apparently predates that marking requirement.

...and it's no longer Code for more reasons than one

While this cable was legal to use at the time it was installed, it no longer meets NEC requirements for a range branch circuit for multiple reasons.  First off, a new installation would require a four-wire (hot, hot, neutral, ground) branch circuit for the range, in order to avoid the shock hazard an open branch neutral poses in a 3-wire range or dryer circuit where the appliance basically "bootlegs" its grounding path from the neutral.

Furthermore, the cable appears to predate the introduction of AA-8000 aluminum alloy conductors, which means that it's made from AA-1350 aka EC aluminum, which is no longer legal for SE Style U cables.  However, a SE cable that does not have a Style marking, while no longer listable by UL, is permitted to be made from AA-1350 as the relevant Code section (NEC 310.106(B)) only applies to SE cables marked as Style U or Style R.

The simplest and most broadly applicable fix for this, provided you can get a 50A GFCI breaker for your panel and have the space available there to install it, would be to replace the existing NEMA 10-50R with an Al/Cu, 75°C rated NEMA 14-50R wired H-H-N with the ground left unconnected, mark the faceplate for the receptacle with "GFCI Protected" and "No Equipment Ground" as per NEC 406.4(D)(2)(c), replace the existing 50A breaker for the range with the correct 50A GFCI breaker for your panel, and convert the range to use a 4-wire cord and plug as per the manufacturer's instructions.  This, at least, will provide GFCI protection to the range to address the shock hazard otherwise posed by not having the range's frame grounded.  You'll need to make sure that all the terminal screws are torqued to the labeled specification torque for that device with an inch-pound torque screwdriver, too, since AA-1350 cable is rather finicky about terminations; a good wire brushing of the wires and a light coat of a listed termination (anti-oxidant, no-al-ox) compound before terminating them would not hurt at all, either.


There are too many unknowns to answer this question. What type of soil is there so a reasonable active pressure, passive pressure, and sliding resistance can be determined? What surcharge is on the 7" slab? How far from the face of slope is the wall located? What is the frost depth? What type of masonry? Grout? Mortar? Reinforcing?

This wall is high enough that a building permit and engineering is required. Do not attempt to design it yourself.  Without all the answers to the above questions, I already know whoever drew the detail is not qualified. The vertical reinforcing is too far apart, and it all should be located on the tension face (soil side) of the wall. There is also a need for horizontal reinforcing in the wall, and vertical and horizontal reinforcing in the footing key. Sorry, but spend the extra bucks to get it designed right.


The 2x4 refers to the rough-cut green wood: it shrinks during drying, then the dried wood is planed smooth, so the finished lumber is supposed to end up at 1.5"x3.5".  While it doesn't really shrink that much, the mills get more usable finished 2x4's from a given tree if they cut them slightly smaller to begin with.

Here's the Wikipedia article about it.


Is it possible to refinish floors one room at a time?

You could install a thin threshold between each room. That would cover the overlap in finish between the rooms.

If the planks run parallel to the doors, you could cut out one board between the two rooms. That would give a clean line between finishes (and place the one board back at the end.

All that said, you will save a TON in labor if you just do it all at once.


What could be causing this electrical issue?

If you are the landlord I would have another electrician come out to check it.  It be something like a factory defect in the subpanel or main panel.  Every lug could be tightened and torqued to factory specs but the lug might be stripped out.

If you are the renter then I would make it clear to your landlord that this is a serious problem and you want if fixed now.

Which ever you are I would have every lug on the ground, neutral and hot sides torqued down to factory specs.  Get the electrician to do a thermal reading while the panel is hot and having the problem.  This would surely cause extra heat where ever it is happening.  If the electrician does that and nothing changes have PGE torque everything on their end and do the thermal reading.

I had the same problem and when they removed the meter and left I removed the Edison side covers and one of the lugs was never tightened on their end but it was a factory connection that was the problem.

Edit On questions on what to use to torque a circuit breaker, see this.  Each breaker has a label on it with the torque rating on it.  At one time there was talk of inspectors carrying torque wrenches with them to spot check circuit breakers, but I know of no electricians own a torque wrench.  When I ask they say just tighten them down as hard as you can and they will pass any test.  My guess is that most residential breakers use about 20 to 25 foot inch lbs per square inch.

Most of the time torquing happens is in industrial plants where they want to get the maximum life out of everything, including breakers.  This is also why thermal cameras are sold to electricians.  Heat spots are bad and most of the time it is a loose connection.

In the OP's case I would definitely use the phrase Torque to specifications, especially if he puts any thing in writing.  His problem can wreak havoc on electronics and motors.


Attaching non-load bearing walls to steel I-beams

You have a few options.
Frame around the beam.
This is probably the easiest method, though it changes the dimensions of the room slightly. Simply build your wall either in front of, or behind the beam. Attach the top plate to the joists.
Weld studs to the beam
You could weld threaded, or non-threaded rods (studs) to the bottom of the beam. Then drill holes in the top plate to align with the rods (studs). If you used threaded rods, use a washer and nut to attach the top plate.
Nuts and Bolts
Drill holes through the top plate and the beam flange, then use nuts and bolts to attach the top plate.
Powder actuated fasteners
You could use powder-actuated fasteners to attach the top plate to the beam.

WARNING: For any method that alters the beam in any way, consult an engineer for fastener schedule, size, and placement.


Can a GFI receptacle die coincidentally at the same time as wall drilling?

I agree that the question is a bit vague. I get the impression you're looking to either accept or absolve yourself of blame for the blowup with the HVAC company. My thoughts:

Sure, coincidences happen. You don't need us to tell you that. GFCI receptacles can last from zero to many days.

It's unlikely that the receptacle was damaged remotely without a heavy load on it, such as a refrigerator. Either a cable was shorted, and that resulted in damaging current through it to some load, or the receptacle itself was damaged. You'd know if the latter was the case, and without forensic analysis you can't know about the former. Of course, it's possible that there are factors you and I don't know about.

Finally, it's odd that you as a tenant got so involved. In the future, let your landowner handle it. Go get a pizza. :)


how to fix an (extremely?) uneven wall before tiling

I would take out/off the drywall if not from the whole wall then from the cabinets up, take off the window trim , casing and sill. Then address any unevenness of the studs with furring strips or shims.  Since the wall is open I would replace all the electrical boxes with the new adjustable depth boxes so you can set them to match your tiled wall. I would then use Denshield in place of drywall, it is similar to drywall, cuts and installs the same, 1/2 thick with a coating on it specifically made for tile. You would only use it where tile would be installed so if the tile will be going all the way to the corner then install it to the corner. If not install it so that it will be just inside ( an inch ) of the tile line so that the texture of the denshield is not visible after tile is installed.  install new casing and sill on the window, straight and true so tiling will be less complicated. if you are wrapping the tile into the window you can use the denshield to case and or sill.


OK, confession time...

I changed the waste pipework to a double connection so I could connect the dishwasher and washing machine.

I forgot to take caps off new waste connection sockets!


How can I repair a chip in partical board table top?

Go to Home Depot or Lowes, in the counter department, pick up some white SeamFil, a putty knife and both some coarse (80 grit) and some fine (220 grit) sand paper.

Sand out the gouge, apply the SeamFil and use the putty knife to smooth it.

After its dried, sand with the fine grit sand paper.

SeamFil


Vertical drilling into ceiling joist for pilot hole

I see your concern but there's really no discrepancy.  The tiny pilot holes you will drill for your #10 screws to mount your projector do not remove any significant amount of material from the joist.  They also don't go all the way through, just an inch or so.  They won't significantly change the strength of the joist.

If you were drilling a 3/4" hole vertically all the way through the joist and running all thread through it, you'd be removing half the material in that spot, and that of course would weaken the joist significantly.

So where do you draw the line?  I am afraid I can't give you an exact answer based on engineering calculations and testing.  However I can give you a rule of thumb that has worked for me.  I find that 3/16" x 3" pilot holes for 1/4" x 3" screws are adequate for anything you can hang off 2x framing, so there's no reason to go any bigger.  That hole is smaller than the shaft of the screw but adequate to prevent splitting in framing lumber, and small enough that it doesn't significantly weaken anything.

I have mounted all kinds of equipment, often hundreds of pounds, using this rule of thumb without any problems.  In the rare instances where I don't trust 1/4" hardware, rather than use larger fasteners, I'll use more fasteners;  for example, sometimes I'll attach unistrut to framing with multiple 1/4" screws then hang the heavy stuff off the unistrut.  This also distributes the load better.


Thermal Expansion and Contraction in Two Story Townhome

That's not right at all. Nothing should be constantly repeating or over that many hours. Usual sounds are just nails sliding in & out of their pockets, 1-pop or crack going in with the cold & 1-pop or crack coming out with the heat, for just a few nails or sounds total. Or, plastic & aluminum siding rustling momentarily in direct Sun. Maybe, it's just the screening on the vents that might be loose & flapping in the breeze.

Get a Carpenter out to check on whether something's actually broken & to sink a bunch of screws & get rid of the usual suspects. Screws don't need to join pieces, they can just span a gap & keep things from moving. Wall & ceiling cracks, if any, are a great indicator of movement areas. Or, it could be something electrical that contracts at night, the Carpenter might notice this, but get an Electrician too.


How can I identify the conductors in an appliance cord with only the green wire colored?

Look for another identifier besides color such as a stripe or rib on one of the two other wires. That will be the Neutral wire. Make sure it connects to the Wide blade on the plug.
Is this because it is AC? No, if it isn't so identified, you are dealing with a cheap knockoff pigtail that probably belongs in the waste bin. In the 120V single phase world, Neutral is effectively at ground potential, therefore if you touch it, you shouldn't get shocked. Hot while alternating isn't at ground potential and so the voltage is alternating between +120V and -120V (RMS, actual voltage peak ±170V), making you the conductor if you connect the hot wire to the dishwasher chassis and you touch it and ground. If the neutral connects to ground in the dishwasher, you've just connected up a dead short.
As this is for a dishwasher, neutral must connect to neutral and hot to hot, any mess-up here is going to be ugly. The only other method is to use an ohmmeter to trace which wire is attached to which blade. Normally narrow blade hot, wide blade neutral and ground pin to ground. If there is no difference in blade widths, then use the socket chart below to figure out which blade is Hot and Neutral from its position and attach the wire to the appropriate terminal in the appliance.
There is only one instance where the connections could be considered even remotely "interchangeable" and that is on a double insulated device where neutral is totally and completely isolated from ground.
NEMA socket listing with blade width and "polarity". Note that NEMA 5-15 and 5-20 can be installed with the ground prong up (coat hanger excluder mode) so right and left slot position is relative.

National Electrical Code 2014
Chapter 4 Equipment for General Use
Article 400 Flexible Cords and Cables
II. Construction Specifications
400.22 Grounded-Conductor Identification. One conductor of flexible cords that is intended to be used as a grounded circuit conductor shall have a continuous marker that readily distinguishes it from the other conductor or conductors. The identification shall consist of one of the methods indicated in 400.22(A) through (F).
(A) Colored Braid. A braid finished to show a white or gray color and the braid on the other conductor or conductors finished to show a readily distinguishable solid color or colors.
(B) Tracer in Braid. A tracer in a braid of any color contrasting with that of the braid and no tracer in the braid of the other conductor or conductors. No tracer shall be used in the braid of any conductor of a flexible cord that contains a conductor having a braid finished to show white or gray.
(C) Colored Insulation. A white or gray insulation on one conductor and insulation of a readily distinguishable color or colors on the other conductor or conductors for cords having no braids on the individual conductors. For jacketed cords furnished with appliances, one conductor having its insulation colored light blue, with the other conductors having their insulation of a readily distinguishable color other than white or gray.
(D) Colored Separator. A white or gray separator on one conductor and a separator of a readily distinguishable solid color on the other conductor or conductors of cords having insulation on the individual conductors integral with the jacket.
(E) Tinned Conductors. One conductor having the individual strands tinned and the other conductor or conductors having the individual strands untinned for cords having insulation on the individual conductors integral with the jacket.
(F) Surface Marking. One or more ridges, grooves, or white stripes located on the exterior of the cord so as to identify one conductor for cords having insulation on the individual conductors integral with the jacket.


Wide back box with central 1-gang mounting

You can get various conversion patresses which will fit over a flush 1-gang box and present a surface 2-gang box, eg

and conversion sockets, eg

If you want to fit a single socket on a double box you'd probably need to use a Euro module faceplate, Euro module socket and blanking plates

If you just need a decorative cover then 'finger plates' are available in white or clear

https://cpc.farnell.com/pro-elec/pel00515/finger-plate-for-light-switch/dp/PL10027


Why do my LED bulbs have such a short lifespan?

I don't know if it's really useful to compare a 120V LED bulb to the stuff you can cobble together from radio shack. First of all the commercial bulbs include a significant amount of circuitry to adjust the voltage, compensate for dimmers, etc. Most bulbs actually accept a wide range of input voltages. And of course with an AC circuit there is no such thing as polarity. Plus the diodes themselves are often quite complicated, mixing various colors and also combining phosphor coatings that are not feasible to do yourself.

But to answer your question about how good they are... I think they're excellent now. I started buying them 5 or 6 years ago when they were $30/each (for high-usage areas only), but the price now is down to about $1/bulb so I don't see why you wouldn't replace every single old-fashioned incandescent at that price. The energy savings will pay for the bulb in only 10 or 20 hours of use.

Also I don't think I've ever had an LED bulb die yet... even using some bulbs in enclosed fixtures even though they're not rated for such usage. (Many bulbs are now, so if you have enclosed fixtures that is something to look for.)