SpudFiles

Here is a combustion that I made for me, my friend name it greener meaner.

Chamber
4" Sch40 27" long
339 CI

Barrel
93" long 2" sch40
C:B of 1.117:1


The cannon has propane injection, it uses a 8" meter pipe at 107psi. The ignition is a BBQ sparker, (also on the cannon that I made for a friend) uses a spark strip type ignition. It will have a chamber fan in there but the one I had melted down.
The stand I made is from 2x3", 24" long 8" wide. Works good. The barrel support is a 8' 2x3 and the barrel is pipe clamp and taped, the wood rests on the stand so that I can take it off and on easy. There is a 2" union on the barrel and cannon so that I can use a burst disk(one or two layers of foil). Feel free to ask questions, here are some pics-







Here is a pic of the stand-

Here is my ammo, a caulk tube that is filled with concrete, really good destroying ammo.



Damage pics-
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It cracked 1 1/2" hardwood plank (was behind target so my garage door didn't break.)

Video-

You have 2 pictures of the stand.

Its pretty nice i would say but i have a question that doesnt deal with your cannon.

When getting the size of the meter, you want it to be 4.2% of your chamber. If not, then you can cut the size of the meter smaller so that you would have to use more pressure. But if it is 4.2% of your chamber, then do you use 15 psi of propane for injection?

im liking it i would like a bigger pic of it though.

LikimysCrotchus5 wrote:You have 2 pictures of the stand.

Its pretty nice i would say but i have a question that doesnt deal with your cannon.

When getting the size of the meter, you want it to be 4.2% of your chamber. If not, then you can cut the size of the meter smaller so that you would have to use more pressure. But if it is 4.2% of your chamber, then do you use 15 psi of propane for injection?

depends on your altitude and so you would use atmospheric + psig

I dont understand.

I live in cleveland, Ohio, USA. So ive been trying to find the atmospheric pressure. What do i do once i know that?

EDIT: My elavation is 173.9 m above mean sea level

i would really like to see some damage pics of what that concrete filled caulk thing can do. hey LikimysCrotchus5 did you watch the game today? cuz the browns lost to the bengals. Go cincinnati (i live there)

Yea Yea, well you know the browns, not the best.

But our basketball team is good along with our baseball team too.

yeah everything in cincinnati basically sucks. look at the reds

I don't understand your question, are you trying to size you meter pipe for your cannon?

The meter can be any size, as long as the pressure is calculated for you chamber size. Like for this cannon the meter needs to be 107psi for the 4.2%, but for my smaller cannon it only has to 54psi to achevie the 4.2%. For your altitude you can use the chart that Boogieman made here- http://www.advancedspuds.com/SpudToolonline.htm but you can just leave it at 14.7psia

If you input all of your specs of your cannon it will calculate you meter pipe at what pressure you should use. If you need anything else let me know.

ok so what if my atmospheric pressure is 14.33? what do i do with that?

EDIT: Nvm i got it all. thx for the link. I knew i saw it b4 but i couldnt remember what site it was.

Hah i still need to get around to fixin my meter pipe steup. I had is up on a shelf in my garage but my sister was an idiot and backed into it with her car. It fell to the floor and busted the guage and bent the street 90. Hahaha, im too lazy . Oh and cheers to Cleveland! I live like 45 minutes away. Crotchus whereabouts do you live in cleveland?

BTW: Nice cannon "WOW!!!", might need a touch up with the paint 8)

Nice cannon, W. Haven't seen you around lately much on these forums, so welcome back for Christmas.

One thing: what's the compressed air input, (male Q.D. on a 1/4" nipple), for on the side of the launcher? Do you use it to displace combustion products with fresh air?

markfh11q wrote:One thing: what's the compressed air input, (male Q.D. on a 1/4" nipple), for on the side of the launcher? Do you use it to displace combustion products with fresh air?

Thanks!
Thats for like you said and also for a gauge set up and a check valve so I can see the pressure it shot at.

Yea the paint needs some help, hopefully today if it sops raining outside.

Merry Christmas

Here are some more pictures-


Inside there that is the spark strip, its a 1" wide section of 1/2'' plywood with nails taped on there to make sparks the whole length of the chamber, hopefully helping with a more even burn.

The wires are attached the to the fittings reducing the need for more holes in the chamber.

That is the switch for the chamber fan.

I will get some videos up soon

Well i am anxious to see

I have a question though, how do you get these cylinders refilled?