First cannon [ TDC-10 ] (with videos now!!!)

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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gwoloshyn
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Wed Dec 26, 2007 12:50 am

I'll go ahead and post here again, that cannon design is AWESOME. I think you did a fantastic job, nice and clean too. Feel free to add some more bells and whistles like propane, but if it was my cannon I would keep it how it is -- nice, light, and easy to handle. I also like the end of the barrel how you have that fitting on there (i suspect thats for looks?) does it affect how you load potatos? I would think you wouldnt get as clean cut.. Anyhow, great work.
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tansit234
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Wed Dec 26, 2007 10:44 pm

Looks beautiful especially for a first cannon. I'm pneumatic only at the moment since I don't want to tackle the propane meter tuning. 13 air powered devices later and I still don't have a smoking gun. I still haven't painted any of my junk :shock: .

I cannot beleive the size of that barrel though. Is it a tennis ball gun :wink: cuz you would have trouble finding potatos over 2" and if memory serves 2.5" is a good tennis ball size.
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nightshot
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Thu Dec 27, 2007 12:02 am

gwoloshyn wrote:I'll go ahead and post here again, that cannon design is AWESOME. I think you did a fantastic job, nice and clean too. Feel free to add some more bells and whistles like propane, but if it was my cannon I would keep it how it is -- nice, light, and easy to handle. I also like the end of the barrel how you have that fitting on there (i suspect thats for looks?) does it affect how you load potatos? I would think you wouldnt get as clean cut.. Anyhow, great work.
That fitting doesn´t affect when i load the potatoes... i use a different mode to load, with cartridges... Look:
[youtube][/youtube]
:D
ralphd
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Thu Dec 27, 2007 4:17 am

That's it?? I think it's supposed to come back out....a little faster and louder.
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nightshot
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Thu Dec 27, 2007 5:28 am

ralphd wrote:That's it?? I think it's supposed to come back out....a little faster and louder.
when i told that i use cartidges u thinked i was talking about bolt action or something else ??? ^^

-------------------------

Hey look at the first post, i added more videos now ! :twisted:
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mark.f
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Thu Dec 27, 2007 9:27 am

He was saying: "Why didn't you shoot it!?"

And to give this post a little "Santa's Helper", to make it a tad longer...
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gwoloshyn
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Thu Dec 27, 2007 11:25 am

Nightshot, please use proper grammer when posting..

And if you have a dremel or a ton of sandpaper, put an inside chamfer on the barrel so when you load the potato from the cartridge it will slide in alot easier and make a much better fit. You'll be surprised how much power you can loose if you don't have a tight fit!
ralphd
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Thu Dec 27, 2007 12:29 pm

If you put the chamfer on the inside of the barrel wouldn't that compress the potato and build up too much back pressure?
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gwoloshyn
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Thu Dec 27, 2007 1:24 pm

ralphd wrote:If you put the chamfer on the inside of the barrel wouldn't that compress the potato and build up too much back pressure?
He's already cut the spud to shape in the cartridge, so once he pushes that into a barrel diameter thats the same as the cartridge, nothing will change. The chamfer is just there to provide a smooth "introduction" for the spud into the barrel for a clean fit..
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nightshot
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Thu Dec 27, 2007 1:32 pm

hey gwoloshyn, thanks for idea, i´m going to do that inside chamfer soon..
:o
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BigGrib
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Thu Dec 27, 2007 2:56 pm

daberno123 wrote:Home Depot won't sell 2.5 pipe. You'll probably have to order it online from BC Arms here
Bull$hit, i get all my 2.5" pipe from homedepot, it's grey sch40 electrical conduit
Yea, that's definitely going to get you at least a tazer.
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mark.f
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Thu Dec 27, 2007 3:33 pm

Yes, for a standard combustion, 2-1/2" conduit will work for a barrel. I've seen the stuff at every Home Depot I've been to. If you do get a barrel from there, and you're still muzzle-loading, do the following two things:

1.) Get a length of pipe with the bell-end still intact. This allows the ball to be loaded easier, for muzzle-loading.

2.) Get a length of 1-1/2" SCH-40 with a coupling or bell-end at the end. This will make a superior ram-rod, because it applies even pressure around the edges of the ball where it meets the pipe, allowing you to load easier. Just a regular broom-stick will compress the ball in one spot, making it jam up frequently during loading.


If you ever build a pneumatic or other high-powered cannon, make sure you use pressure-rated pipe for the barrel, and not conduit. Also, if you use any long lengths of the pipe for a barrel, make sure it's supported properly. Conduit is more rigid than regular PVC, but it's also a little more brittle.
ralphd wrote: If you put the chamfer on the inside of the barrel wouldn't that compress the potato and build up too much back pressure?
All materials which *should* be used for making combustions can withstand a full closed-chamber ignition, even DWV once or twice, (unless subjected to shock or physically damaged).
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gwoloshyn
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Sun Dec 30, 2007 2:40 pm

Haha, nice videos man. Where do you live?

Thats a really fine cannon you have there.. What are you using for propellant?
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nightshot
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Sun Dec 30, 2007 10:51 pm

gwoloshyn wrote:Haha, nice videos man. Where do you live?

Thats a really fine cannon you have there.. What are you using for propellant?
thanks... I am brazilian but i live in japan.... and I am using a deodorant spray now .... :o
jackh
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Wed Jan 23, 2008 6:49 pm

you said you use propane, but you spray something out of an aerosol can in your vids... am i missing something here?
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