<p>I think you only lacked the right search term. I found this by searching for &quot;transparent internal pvc ball cap&quot;:</p>
<p><a href="https://i.sstatic.net/bJq7vm.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/bJq7vm.jpg" alt="enter image description here" /></a></p>
<p>It fits inside a PVC pipe, which has an inside diameter of 1-1/4&quot;. The only manufacturer I could find is Formufit. Here's <a href="https://formufit.com/products/1-1-4-in-furniture-grade-pvc-internal-ball-end-cap?variant=38113744027797" rel="nofollow noreferrer">their web shop</a> (<em>I am in no way affiliated with this manufacturer or shop</em>).</p>
<p>This seems like it could be a standardized product, designed to fit standardized PVC pipes. So maybe you could find it in different web shops or in your local home construction store.</p>
<p>There are also <strong>dome lenses</strong> that might fit and if you're ok with the cap being metal instead of transparent plastic, you could have a look at <strong>hand rail end caps</strong> and find a lot of different designs and sizes.</p>
<p>If all else fails, consider 3D printing a cap with a <strong>resin printer</strong> using the smallest available layer thickness. The resolution of these printers is enough to create a transparent object with only a slightly matte surface.</p>

CC BY-SA 4.0
2022-01-13T10:02:50.017Z
The original photo shows debossed lettering of 110 mm diameter, slightly larger than 4 inches. This makes your suggestion for 3D printing useful. Post processing of transparent resin printed items can approach substantial clarity.
fred_dot_u
CC BY-SA 4.0
2022-01-14T00:17:48.150Z
There are three problems however. The first is that I don't live in the USA and I haven't found any info about shipping to other countries. The second is that my pipe isn't 1-1/4 inch. And the third is that the solid angle of the spherical cap in this is much larger. From what I see this is virtually half a sphere, or 2π steradian. The solid angle of the spherical cap in my fan is about 1.28π steradian. Of course, I could buy one and cut a cap from it, but then again I'd need it to be a sphere of about 27 mm in diameter, and this one is pretty bigger. And I could find similar in my country
user2934303
CC BY-SA 4.0
2022-01-13T06:55:02.510Z
2022-01-13T08:42:12.153Z
2022-01-13T08:42:12.153Z
Elmy
<p>I'm restoring an old fan that used a horseshoe-shaped steel pipe for the base, and the ends of this pipe are closed of with two caps.</p>
<p>The caps are made of a transparent plastic, their shape reminding of a &quot;mushroom&quot;, like this piece:</p>
<p><a href="https://i.sstatic.net/2J7vV.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/2J7vV.png" alt="enter image description here" /></a></p>
<p>This piece is hollow and inside there's another spherical cap made of polished chrome steel.<br />
So when it's fitted in the pipe you can see a transparent spherical cap and inside it the chrome spherical cap.</p>
<p>The issue is that the plastic cap is broken and damaged.</p>
<p>From photo analysis I determined that the plastic cap can be cut from a 27 mm diameter sphere.</p>
<p>Now there's the issue: I don't know where to get a transparent, plastic hollow sphere 27 mm in diameter.</p>
<p>A hollow sphere 25.4 mm (1 inch) in diameter would also work, I'd only have to cut a spherical cap with a slightly larger solid angle. It wouldn't be identical, but close enough.</p>
<p>The issue is that I can't find anything or anyone that sells this.<br />
I've only found some hollow transparent spheres used for Christmas decorations, but none 1 inch in diameter.</p>
<p>I'm trying to figure out how could I make one.</p>
<p>Do you have any idea?</p>

CC BY-SA 4.0
2022-01-13T06:03:49.633Z
Welcome to Arts & Crafts! If you have a picture of the damaged cap, adding that to the question would help a lot.
Elmy
CC BY-SA 4.0
2022-01-13T07:13:37.570Z
Hi, this type of question is actually off-topic here per our [Help]: "*Product and service recommendations ("Where can I get [product]?" or "Where can I find someone who does [service] in [area]?")*". If you can [edit] your question to *only* ask how you could create one yourself, it would be completely fine. Thank you for your understanding, and welcome to Arts & Crafts!
Joachim
CC BY-SA 4.0
2022-01-13T07:59:18.960Z
@Joachim I don't agree with you. It's asking "How / where can I get an object that looks like this and has those properties for my craft project?" not "Where can I buy an [insert product name here]?".
Elmy
CC BY-SA 4.0
2022-01-13T08:20:20.497Z
@Elmy Yes, I realized, I'll edit it myself and open it again. I noticed directly afterwards, but had something more pressing going on. The "where" is still off-topic, though, and I think closing a question simply because it requires editing is a perfectly fine reason for closing it, right? (An honest question - not a criticism :) But, to be fair, this also makes your answer off-topic.
Joachim
CC BY-SA 4.0
2022-01-13T08:38:11.257Z
@Joachim I know that many sites close questions quickly for many reasons and editing can be one of them. Worldbuilding even has a sandbox for closed Qs. But I personally am not a big fan because it send a negative signal to the OP. Especially new contributors abandon their questions before they notice the reopening or any answer. As to my answer, I wouldn't have written it if I thought it was off-topic ;). But there are different opinions about links to web shops (in my main community [Pets](https://pets.stackexchange.com/) it might have been flagged as spam without the explicit disclaimer).
Elmy
CC BY-SA 4.0
2022-01-13T08:44:06.940Z
@Elmy Yes, I know, and I also realize my position in this matter tends to sway. This is mostly because closed questions have a bad reputation among all users, but actually shouldn't be regarded as something negative in the first place (which is something I think I should bring up at Meta). But yes, good point about your answer :)
Joachim
CC BY-SA 4.0
2022-04-02T03:18:17.913Z
If a good end cap can be removed without breaking it, it can be used to make a mold, then cast a new one.  It may also be possible to repair the broken one.  More details would be needed, though, to describe a solution.
fixer1234
<plastic><material-sourcing>
How can I make hollow transparent spheres between 25 and 29 mm diameter?
user2934303
# How can I make hollow transparent spheres between 25 and 29 mm diameter?

(Asked by: username_0 on 2022-01-13)

I'm restoring an old fan that used a horseshoe-shaped steel pipe for the base, and the ends of this pipe are closed of with two caps.

The caps are made of a transparent plastic, their shape reminding of a "mushroom", like this piece:

[![enter image description here](https://i.sstatic.net/2J7vV.png)](https://i.sstatic.net/2J7vV.png)

This piece is hollow and inside there's another spherical cap made of polished chrome steel.  
So when it's fitted in the pipe you can see a transparent spherical cap and inside it the chrome spherical cap.

The issue is that the plastic cap is broken and damaged.

From photo analysis I determined that the plastic cap can be cut from a 27 mm diameter sphere.

Now there's the issue: I don't know where to get a transparent, plastic hollow sphere 27 mm in diameter.

A hollow sphere 25.4 mm (1 inch) in diameter would also work, I'd only have to cut a spherical cap with a slightly larger solid angle. It wouldn't be identical, but close enough.

The issue is that I can't find anything or anyone that sells this.  
I've only found some hollow transparent spheres used for Christmas decorations, but none 1 inch in diameter.

I'm trying to figure out how could I make one.

Do you have any idea?

**Tags:** plastic, material-sourcing

> **Comments:**
> **username_1**: Welcome to Arts & Crafts! If you have a picture of the damaged cap, adding that to the question would help a lot.  
> **username_2**: Hi, this type of question is actually off-topic here per our [Help]: "*Product and service recommendations ("Where can I get [product]?" or "Where can I find someone who does [service] in [area]?")*". If you can [edit] your question to *only* ask how you could create one yourself, it would be completely fine. Thank you for your understanding, and welcome to Arts & Crafts!  
> **username_1**: @username_2 I don't agree with you. It's asking "How / where can I get an object that looks like this and has those properties for my craft project?" not "Where can I buy an [insert product name here]?".  
> **username_2**: @username_1 Yes, I realized, I'll edit it myself and open it again. I noticed directly afterwards, but had something more pressing going on. The "where" is still off-topic, though, and I think closing a question simply because it requires editing is a perfectly fine reason for closing it, right? (An honest question - not a criticism :) But, to be fair, this also makes your answer off-topic.  
> **username_1**: @username_2 I know that many sites close questions quickly for many reasons and editing can be one of them. Worldbuilding even has a sandbox for closed Qs. But I personally am not a big fan because it send a negative signal to the OP. Especially new contributors abandon their questions before they notice the reopening or any answer. As to my answer, I wouldn't have written it if I thought it was off-topic ;). But there are different opinions about links to web shops (in my main community [Pets](https://pets.stackexchange.com/) it might have been flagged as spam without the explicit disclaimer).  
> **username_2**: @username_1 Yes, I know, and I also realize my position in this matter tends to sway. This is mostly because closed questions have a bad reputation among all users, but actually shouldn't be regarded as something negative in the first place (which is something I think I should bring up at Meta). But yes, good point about your answer :)  
> **username_3**: If a good end cap can be removed without breaking it, it can be used to make a mold, then cast a new one.  It may also be possible to repair the broken one.  More details would be needed, though, to describe a solution.  

---

## 1 answers

### Answer by username_1 on 2022-01-13. Score: 2

I think you only lacked the right search term. I found this by searching for "transparent internal pvc ball cap":

[![enter image description here](https://i.sstatic.net/bJq7vm.jpg)](https://i.sstatic.net/bJq7vm.jpg)

It fits inside a PVC pipe, which has an inside diameter of 1-1/4". The only manufacturer I could find is Formufit. Here's [their web shop](https://formufit.com/products/1-1-4-in-furniture-grade-pvc-internal-ball-end-cap?variant=38113744027797) (*I am in no way affiliated with this manufacturer or shop*).

This seems like it could be a standardized product, designed to fit standardized PVC pipes. So maybe you could find it in different web shops or in your local home construction store.

There are also **dome lenses** that might fit and if you're ok with the cap being metal instead of transparent plastic, you could have a look at **hand rail end caps** and find a lot of different designs and sizes.

If all else fails, consider 3D printing a cap with a **resin printer** using the smallest available layer thickness. The resolution of these printers is enough to create a transparent object with only a slightly matte surface.

> **Comments:**
> **username_4**: The original photo shows debossed lettering of 110 mm diameter, slightly larger than 4 inches. This makes your suggestion for 3D printing useful. Post processing of transparent resin printed items can approach substantial clarity.  
> **username_0**: There are three problems however. The first is that I don't live in the USA and I haven't found any info about shipping to other countries. The second is that my pipe isn't 1-1/4 inch. And the third is that the solid angle of the spherical cap in this is much larger. From what I see this is virtually half a sphere, or 2π steradian. The solid angle of the spherical cap in my fan is about 1.28π steradian. Of course, I could buy one and cut a cap from it, but then again I'd need it to be a sphere of about 27 mm in diameter, and this one is pretty bigger. And I could find similar in my country  

---

