Today (saturday and sunday roll up) I spent some time playing with the new hardware I bought from ACS. I had ordered a bunch of new bolts. KP3's for the Aileron Slave strut arms, AN665 forks for the drag wires ect. I also bought some 0.063 4130N to make backing plates for the Aileron hinges that I will rivit 1/4-28 nut plates into so that I can tighten the aileron block down the road without cutting a hole in the fabric in the future.
I also spent a bunch of time playing with the geometry of the 90 deg bellcrank location. It's a rather tight area between the drag wire and the bell crank. I studied the photos on raven's website a bunch and finally came to the conclusion that that the aileron hinge needs to be on the inboard side of the I-strut hole. I also figured out how far inboard after figuring out where center was. The edge of the outboard side of the aileron hinge block will be set 0.3125″ inboard of the I-strut hold centerline. And the aileron attach bolt centerline will be 0.8125″ inboard of the I-strut hole centerline. With the aileron hinge on the inboard side of the the I-strut hole pushes the 90 deg bellcrank past the I-strut 1/4″ doubler by about 0.5″ so I will have to glue in a small amount of 1/4″ to extend the doubler a little to accomdate the new location of the 90deg bellcrank.
After figuring all this out I realized I had made a mistake assembling the wings originally. The ribs unfortunatly matter which way is up on the lowers. This wouldn't normally matter on a symetrical rib (and doesn't for the top wing) but the way the truss is set up there happens to be a nice gap as the truss goes the opposite side for the control push rods. One wing I got resonably lucky and only screwed up 2 ribs the other wing I screwed up 3 ribs.
I have two courses of action here both are just fine one is easier both are likely the same strength.
Today I cleaned up all the excess glue on the fore and aft spars on the left wing with a file in preparation to mark and drill the holes for the metal wing root strap. I basically did the same thing as I did on the right wing that is marking the 1/2″ up and 1/2 inboard hole and then placing the whole thing in the drill press. I then drilled out the other three holes in the drill press using the strap as a guide. It went pretty quickly (the drilling that is, the cleaning up of the glue took forever). I then spent some time filing the excess glue off the I-strut doublers in preparation to drill and install the flying wire crush plates.
After I did all that I started playing with the 90deg bell crank and the aileron hinge location. The bell crank is going to be very close to the drag wire. I will need to talk to Raven about how to orient this. No pictures today as I have taken some for the right wings and it is the same just mirrored.
Today I spent a fair amount of time figuring out how I was going to drill these holes straight. Finally I just decided to put the hole wing in my drill press. It worked out awesome the holes were nice and straight and lined up just right.
Today I spent time removing the excess glue that spilled out of the ply root doublers with a file. It was pretty easy and I got it looking very clean. I then spent some time figuring out how i was going to drill the holes for the root straps. I have a copy of the S-1D drawings and the rear spar strap location is different than the S-1S drawings. I finally emailed a Stuart and he told me to put the strap at 1/2″ up and 1/2″ inboard and then make the strap flush with the top surface of the spar. Easy enough. On the front spar I did it to the drawing.
Today I received all the rest of the hardware from Raven Aircaft. This included the aileron hinges, bellcranks, Idler, spar straps, drag wire lugs, aileron drive arms, and aileron hinge brackets. I also had Raven powder coat them in white, which turned out really nice I highly recommend doing this.
I then set off to glue the spar ply doublers at both wing roots. I wanted to apply equal pressure so I coated them with T-88 and used plastic wrap to keep my 2X4 from sticking and then I used two clamps per root.
After yesterday was shot due to the all important Beer Pong Championship (which I won!) I nursed my hangover till about 4 in the afternoon and then decided to tackle the right wing tip. It went a whole lot faster than the left tip because I had already done the hard work in figuring out the geometry on the left. So basically rinse and repeat on the wing tips. Both are looking pretty Sharp!
Tonight looking for more to do I decided to drill out I-strut holes through the top doubler completing the I-strut holes I also reamed them out to 17/64 all have left to do there is tape of the bottom fill the hole up with T-88 to seal it up and I will ream it again to the final size. I also trimmed the corner blocks that fit next to the I-strut doublers so that they would fit between the doubler and the rib.
Searching for more to do I decided to figure out the wing tip geometry and fitting. I had to slide the tip rib about 1-1/8″ more inboard that so that I didn't have cut into the tip rib nose far so the final tip will transition nicely. After that I started to taper the spar and cut to size. I started with the front spar and made the 45 deg cut I initially did this with my coping saw and two pieces of aluminum strip to guide it. It worked but was a little ugly so I had an idea to use my powered miter saw to clean it up and that worked surprisingly well. I then used the saw to cut the rear spar which also worked well. I trimmed the tip rib and the tip bow so that I could fit it up and temporarily nailed the bow to the spar everything looked great. I then trimmed the spar using my coping saw again and steel plates as guide on both sides. This also worked really well. I sanded the spar smooth.
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