My 12 dollar presssure chamber

[Dale Allen]

Well, it took me long enough! I had this idea in my head for some time and finally proved it out. I already had the air compressor that I use for various nail guns. I spent about 12 dollars on the short pipe and fittings. It has limitations of course. I just didn't want to go the pressure pot route just yet. Although, now that I see what can be accomplished, I'm sure I'll buy one in the near future. This is a chamber that is 1" in diameter and half a foot long so it will accommodate 2 blanks at a time. I did a test run with some alumilite clear and except for 2 small bubbles on the outer rim it is absolutely clear. Well OK, there are some other contaminates in there because I didn't take the time to really clean it out first. I also did not try to get any of the bubbles out prior to the pour and I stirred rapidly so there were intentionally big and small bubbles. This was in for 2 hours at about 50 PSI. I'm happy now cause I can use a clear resin that doesn't smell up the whole house.
The chain clamp is the solution to keeping the chamber fixed while I screw on the coupler and the mold doesn't spill.
Now I can get on with making blanks.

 

[Wood Butcher]

Very inventive. Sounds like you're onto something here. May I ask, what mold were you using to cast in?
Thanks
WB

 

[Dale Allen]

Bill, the test was just with a short piece of plastic tube and I just plugged the end and cut out the side. I am in the process of making RTV silicone molds for the 2 sizes I will be using for now. I struggle a bit with that process as I am not used to thinking backward or in reference to a mirror image pf the finished project. Takes me a bit longer, but I get there.

 

[Wood Butcher]

I've made several of the RTV molds and some from the nylon cutting board material and I think I prefer the RTV. They both work ok but the RTV seems more forgiving to me. I tried one made from plywood and covered with clear packing tape but wasn't too pleased with it.
I wonder if there would be a way to "mount" the chamber vertically so PVC pipe could be used. When time allow I may give it a try, thanks for sharing the idea.
WB

 

[Displaced Canadian]

I clamp mine to a cross brace that runs between the legs of my work bench.

 

[sschering]

Cool.. I've been planning to make the same thing..
I was planning to go vertical and use PVC pipe molds I can drop in.

 

[Priusjames]

These things rarely make it out of my mind...nice job, and thanks for sharing.

 

[Dale Allen]

Just as a side note.
I went to the blue box today with intentions of getting a 1.5" piece of pipe, cap and reducer coupling to make this a little bigger. I was stopped dead by the fact that they do not carry any fittings in that size and very few larger than 1".
I guess I'll need to visit the local 'real' hardware store and have them make me an 8" piece.
The reason I want to do this is because it is a very tight fit to make a mold for the 1" ID.