Intro and a combustion cannon

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Heimo
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Tue Oct 27, 2009 2:36 pm

Ok I am new here. My name is Heimo I am a South-African and I have been playing with spud guns for more than 3 years now.

here is my current combustion cannon
Image

I use methylated spirits for fuel and had great results using it the cannon is made from an old propane tank with a steel pipe welded to it as a barrel. The small thing sticking out the side is a small combustion chamber this spud gun works on the following principle I have 2 combustion chambers one small one (made from pipe fittings) and the big one (the propane tank) how it works the small chamber explodes into the larger one causing all the fuel to ignite at once even without a potato in the barrel this thing makes a report load enough to make your ears ring for a few minutes I believe this two stage method to be a secrete to a high power spud gun I have had a spud gun made from a larger tank that had LESS power than this thing I don't know if someone else have used a concept similar to this one before if someone have please show it to me.

I am busy developing a new type of cannon but that is classified until I get it finished (I haven't even started it yet cause I got too many projects at the moment)

one of my other hobbies is metal casting in aluminum, brass, bronze and soon Iron Here is a pic of an old casting I made it is supposed to look like an old black powder cannon
:)
Image

I want to make the combustion chamber for my new cannon from a casting but that is another thread

Some thing that I want to state is I will never make a cannon out of PVC or any kind of plastic I just don't trust it I may be paranoid but rather paranoid than have a cannon blow up in my face all of my previous cannons had been made from some kind of pressure vessel and I think I am going to keep with that tradition. If you guys want any info on making molds to cast metal in or any questions in that category I would be glad to help

Heimo
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jackssmirkingrevenge
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Tue Oct 27, 2009 2:39 pm

Interesting concept, some damage pics illustrating the increased power would be appreciated ;)

Since you're new, we'll forgive the failure to edit out your feet in the picture :roll: :wink:
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Heimo
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Tue Oct 27, 2009 2:45 pm

I will have to find something to shoot tomorrow I left out that the barrel have a 25mm bore so it ain't that big this site do indeed have a lot of info on it I think that my next design will be even more powerful
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vardas
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Tue Oct 27, 2009 10:04 pm

very nice!, do you use the smaller chamber as a handle? how do you ignite it? & what do you use for ammo? id like to see some damage pics and maybe a few close up pics of your cannon. welcome to spudfiles p.s. ever cast chess pieces?
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grock
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Tue Oct 27, 2009 11:55 pm

jackssmirkingrevenge wrote:Interesting concept, some damage pics illustrating the increased power would be appreciated ;)

Since you're new, we'll forgive the failure to edit out your feet in the picture :roll: :wink:
i thought we were supposed to have our feet in the picture :P
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jackssmirkingrevenge
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Wed Oct 28, 2009 12:25 am

grock wrote:i thought we were supposed to have our feet in the picture :P
GAAAAAH!

I try to show my launchers and only my launchers in my photos and videos, it's not that much of an effort and I wish everyone could do the same. Hey, at least feet aren't underpants or pets, both of which have appeared on the forum :roll: :D
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Wed Oct 28, 2009 12:28 am

Just as an FYI, your "dual chamber" design has a name. Or rather, the smaller chamber has an accepted name in the combustion sciences world: jet igniter.
Simulation geek (GGDT / HGDT) and designer of Vera.
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Technician1002
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Wed Oct 28, 2009 12:36 am

I have an antique gas engine that uses this principal. The spark plug is in it's own little chamber. The passage to the cylinder is about the size of a pencil lead. The engine works well. It suprised me when I removed the plug only to find a small marble size space inisde with a hole out the back to the chamber.
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Heimo
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Wed Oct 28, 2009 11:27 am

vardas wrote:very nice!, do you use the smaller chamber as a handle? how do you ignite it? & what do you use for ammo? id like to see some damage pics and maybe a few close up pics of your cannon. welcome to spudfiles p.s. ever cast chess pieces?
Yes I use the smaller chamber as a handle the damage pic was scheduled for today but we had a electric storm early this morning and it knocked out our internet so I spent today getting it fixed might still get to play a bit

"p.s. ever cast chess pieces?"

no but it won't be hard to do so

"what do you use for ammo"

anything that fits the barrel but normally I just use plain potato

I will try to get a damage pic today or tomorrow.

Heimo
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vardas
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Wed Oct 28, 2009 2:28 pm

thats cool, ragnaroc makes these miniature figurines & posts them on this site. so should you. but what do you ignite with? its kinda hard so see in your first picture .cant wait to see some damage pics ,maybe a close up pic of your cannon
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Heimo
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Thu Oct 29, 2009 10:43 am

Ok here is the first damage pic
Image

that was a piece of 1/2 plywood now I know that ain't much compared to some of the stuff on this site. but I am looking for something better to shoot at the projectile is still missing it kept on flying so I am still looking for it

I am going to make a new projectile and go get another damage shot when I am finished posting this
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Ragnarok
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Thu Oct 29, 2009 10:54 am

jackssmirkingrevenge wrote:Hey, at least feet aren't underpants or pets
Or pets wearing underpants... :shock:

But I'm being off-topic.

I like the cast cannon - not quite so endeared to the slightly unwieldy looking combustion, but as long as you're okay with it, that's all it needs to be.
Does that thing kinda look like a big cat to you?
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jackssmirkingrevenge
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Thu Oct 29, 2009 11:12 am

Heimo wrote:that was a piece of 1/2 plywood now I know that ain't much compared to some of the stuff on this site.
Still something to be proud of though :)
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Heimo
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Thu Oct 29, 2009 11:17 am

Ragnarok wrote:
jackssmirkingrevenge wrote:Hey, at least feet aren't underpants or pets
Or pets wearing underpants... :shock:

But I'm being off-topic.

I like the cast cannon - not quite so endeared to the slightly unwieldy looking combustion, but as long as you're okay with it, that's all it needs to be.
I know it is a little different but if you think that one is looking strange wait till you see the next one :D

here is one more pic for your enjoyment
Image

this was the lid of a wood ammo crate unfortunately I aimed a little high so I have just blown the top off :lol:
I am gonna take one more shot at it and I will post a pic later

BTW I have not measured how thick that lid is yet but it seems close to 20mm thick solid wood
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qwerty
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Thu Oct 29, 2009 11:21 am

Cool!, was that just with a spud and also did it go through or just shatter it?
Pretty good cannon if you ask me :)
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