Simple Clear Combustion.

[Biopyro]

I had some spare time in the workshop and some acrylic pipe hanging around so I thought I'd put together a nice cannon. What else could I do with it!?

It's a 90mm chamber with 40mm barrel, using PVC fittings. PVC cement is sufficient for bonding the plastics.
Both the chamber and barrel are 5mm wall thickness, which is pretty chunky. I would not be comfortable going thinner with the chamber, but I definitely could have gotten away with 3mm for the barrel. I tend to just use a regular PVC barrel as a result.

It has a tyre valve for easy fuelling with metered propylene (MAP-PRO), and two electrodes connecting a BBQ igniter to a foil-tape spark strip. The spark strip is peeled up from the wall to prevent skirting, and runs the length of the chamber down two sides. There are 5 gaps.

The cleanout cap is kept well lubricated and spins off very easily for venting. The barrel is pushfit, incredibly easy to remove. Unfortunately this means that the barrel can pop off when it is allowed to get wet.

Pictures (click for full size):









Videos:

[youtube][/youtube]
From 0:40s
http://youtu.be/Ez9hnlNu2Yg?t=40s

[CS]

simple=best

Nice construction. Wish I had some clear pvc lying around.

[spudamine]

looks nice, a LED fan inside would add to the pimp factor
I recently saw those ignitors appear on ebay and bought one on a whim, it's fantastic . Mine fires at approximately 10Hz, it's defintely making me feel like it's time for a full-auto combustion.

[AircannonSweden]

Nice one Where did you get that cler tube?

[Biopyro]

Ooops, forgot to mention - it was in the title. The chamber and barrel are actually acrylic. I felt comfortable because despite the reduced impact strength, it is still a strong material, and 5mm wall thickness is pretty tough for a relatively un-optimised cannon.

Yeah, I am really pleased with the igniter. Enough to rave about it in another thread even!