D V1.0

Boom! The classic potato gun harnesses the combustion of flammable vapor. Show us your combustion spud gun and discuss fuels, ratios, safety, ignition systems, tools, and more.
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Buntyspudbaby
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Tue Aug 05, 2014 5:55 am

I would like to present to you all, Deuteragonist. It is a modest sized advanced combustion. Metered propane, chamber fan, 3 ignition points and rubber for protection, and insulation.
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I designed the cannon to shoot golf balls. The 40mm diameter barrel suits them perfectly and has indentations, two to stop the ball entering the chamber and three in front of them which are less pronounced to wedge the ball in place. I saw the detent tool and liked the idea, so I whipped up my own one.
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The chamber volume is 95 cubic inches. It is 50mm in diameter and I put it together in sections.
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One section of which I installed the chamber fan is a threaded coupler with a joining piece of pipe glued in place. I terminated the power cables through the mounting bolts. The elbow section was put together the same way, with one joining piece glued in place. This allowed me to drill and thread the brass nipple into place. For this I used a 19mm spade bit, and a non tapered threaded brass pipe (the thread was the entire length of this pipe) was used to stretch a thread into the hole. I was aware once I had threaded the hole, that the way which I did this did not produce full thread depth and the nipple was not protruding far enough inside to place a nut. So I mixed some epoxy and coated the brass nipple, and the space between the male and female thread allowed a good amount of epoxy the entire thread length. I then surrounded the nipple inside the pipe with epoxy, enough to create a flat surface.

All of the pvc exterior has a pn18 rating, and the joining pipes have a pn9 rating.
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Last edited by Buntyspudbaby on Tue Aug 05, 2014 6:46 pm, edited 2 times in total.
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jrrdw
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Tue Aug 05, 2014 7:43 am

Nice work! :D
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jackssmirkingrevenge
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Wed Aug 06, 2014 9:42 am

Nice! Those first two rounds through the same hole were awesome :D

How thick was the target material?
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Talk
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Wed Aug 06, 2014 1:12 pm

Nice but why only 20 psi? more psi more fun :)
How thick was the target material?
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I think this was target material measurement.
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Buntyspudbaby
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Wed Aug 06, 2014 7:20 pm

Thank you.

Yes, 14mm plywood (2 pieces of 7mm)

:wink: I was happy with a hit on the board at the time, but I could add some sights and do some long distance shots? Maybe a video for the future.
"Unable to comply, building in progress." - Westwood studios.
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Buntyspudbaby
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Thu Aug 07, 2014 4:43 pm

Talk wrote:Nice but why only 20 psi? more psi more fun :)
As the name suggests there will be larger volume in the future :)
Last edited by jrrdw on Fri Aug 08, 2014 6:17 am, edited 1 time in total.
Reason: Fixed quote tag.
"Unable to comply, building in progress." - Westwood studios.
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