My 'Mr.Howitzer'

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.
queensland spudder
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Thu Sep 03, 2009 4:06 am

This my first Cannon i built it a few years ago. this cannon is really good for it's weight and power considering it's small chamber . This can launch tenis balls up to 200m. I shot a piece of plastic about 50mm in dia and wraped it in cloth to make a tin can go concave. The crude sight also works ok

Cannon specs.

Chamber size. 100mm/4 inch
Chamber length 290/11.4 inch

Barrel size 65mm/2.5 inch
Barrel length 1210mm/47.65 inch

C:B ratio 0.64:1
Attachments
Aluminum can hit 3.JPG
Aluminum can Hit 2.JPG
Aluminum can Hit 1.JPG
Small Cannon (sight shot).JPG
Small Cannon.JPG
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Moonbogg
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Thu Sep 03, 2009 4:13 am

Looks like fun. Any other builds up your sleeve?
queensland spudder
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Thu Sep 03, 2009 4:54 am

i might have rebuild my 50mm cannon after the end cap ruptured into pieces and the chamber has a neatly made crack in it , it was a good one it was light as and it had a a bit of a kick when i fired to :D
Last edited by queensland spudder on Thu Sep 03, 2009 7:35 pm, edited 1 time in total.
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FORE!!!!
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Thu Sep 03, 2009 5:17 am

Its official,that the most ghetto sight ive ever seen,lol :D

i pressume your mounting your piezo into the centre of your threaded cap,not a good idea as this further weakens ,the weakest part of your launcher.
have you thought about using screws to create the spark gap in the twin layer of pipe,where your junction connects to your reducer?,it probly would create dodgy ignition altho its alot safer than mounting the piezo in the cap.
maybe even where your end screw cap meets the junction,just a thort :)
al-xg wrote:
I've used various things like cutting oil, silicone lubricant, even butter

jsr wrote:
This collection of containers on your bedside table must look very intimidating to any visiting young ladies

...but hey, lube shows you care;)
queensland spudder
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Thu Sep 03, 2009 4:18 pm

i will consider that option FORE, however is there any way to reinforce the cap with anything, Cause i really like the way i can separate the ignition system from the cannon so i can clean it and not wreck the ignition.

But i think the reason why the cap failed is cause the round i put in the cannon was to tight and had a bit of banging to get i down the barrel. It was cold maybe 3-5 degrees Celsius so i guess that's what cause the cap to fail cause after 2-3 years of firing it was still in good condition.
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spudtyrrant
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Thu Sep 03, 2009 4:26 pm

FORE!!!! wrote: i presume your mounting your piezo into the centre of your threaded cap,not a good idea as this further weakens ,the weakest part of your launcher.
just like the good old days http://www.spudfiles.com/forums/golf-ba ... 18646.html
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FORE!!!!
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Thu Sep 03, 2009 5:18 pm

spudtyrrant wrote:
FORE!!!! wrote: i presume your mounting your piezo into the centre of your threaded cap,not a good idea as this further weakens ,the weakest part of your launcher.
just like the good old days http://www.spudfiles.com/forums/golf-ba ... 18646.html
ya live and learn :D ,altho ive never had a cap blow off on me, it looks way more funky and is alot more safer.... :)

"i now see the light,step into the light son" :wink:
al-xg wrote:
I've used various things like cutting oil, silicone lubricant, even butter

jsr wrote:
This collection of containers on your bedside table must look very intimidating to any visiting young ladies

...but hey, lube shows you care;)
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