SpudFiles

Gday all
ive got a small fire extinguisher dunno the size ive previously used it to shoot bits of wire in an over under set up i removed the gauge and inserted a valve. now i was wondering if it would be able to shoot projectiles such as marbles ive got the perfect steel pipe i found at tafe. also i was wondering if i should keep the trigger it has on their or extend the chamber and have the trigger elsewhere and atempt a piston trigger.

Well if its your first cannon, i'd say keep it on, others will say attempt piston valve, most piston valves need a high flow air source to help seal them *correct me if im wrong. but i'd keep the trigger on there, OR get a 1" sprinkler valve, and pneumaticly mod it (do some searching, using the wiki button, or the Spudfiles search button), and yeh.

What do u mean you "removed the gauge, and inserted a valve" u mean you took the gauge of it, and put a tire valve/shrader valve in (fill valve)?

~thursto

spot on mate exactly what i done. do u think it will be able to shoot marbles

Yeah i think it'd be able to shoot marbles, just have your barrel like almost 2 times as long as ur chamber, and it should be good. pump it to a high PSI, well im not sure what the fire extinguisher valve is pressure rated to, but i think 50PSI would be ok (thats not a hig PSI, jut recomended that because i dont know how much PSI it can handle), just be careful with it, make sure you seal everything correctly and dont drop it when its pressurerised.

yer earlier i used a hand pump and got it to 75 i reckon it could go higher than that tho because i didnt really try how powerfull do u reckon it would be

Well im not sure how powerful it would be, but my cannon, has a marble barrel (1/2" Pressure PVC) and a 2" pressure PVC chamber, at 80psi from 20m it can put a marble through some ply wood. Just test it out, ad let me know, andget some pics and a vid so we can see the lil beast !

~ Thurso

ok will do the only prob i face is trying to get the pipe joined to the chamber last time i just got a copper elbow that had a fitting on one end that went around small pipe then a bit screwed on over it this time ill have to figure out something hell smart lol. good old Aus if only we could legally make these lol

i wrote a post not long ago under the name bugmenot about the same topic, now ive got a different account plus pics. My question was does any one have any ideas regarding joining the two pieces together? [/img]

does anyone got any ideas what i should do ?

Not so sure about joining them, but it helps to drill out the nossle hole to increase flow.

that sounds like a good idea i might have to have a look at doing that 2morro, also ive decided to decrease the barrel size down to shoot darts instead and ill save that other bit of pipe for a future project.

Oh yeah go the darts!! So much fun!
Use coat hanger's (readily available) , heat treat the tip's if you can/are familiar with hardening.. find beads at local thrift store's, that fit your tube and have a hole in them slightly larger than the wire...
Crimp the back end so the bead won't come off... Sharpen and use...
I find adding some 6mm fishing sinkers, helps for penetration purposes... I put 3 on my 30cm hunting dart's...
I'd post a pick but I just warped my last one, trying to get through 1 1/2 in pine stud at 180 psi... One here going 15cm through 1/4 ply..
http://www.spudfiles.com/forums/viewtop ... tml#136843

sweet how accurate are those darts and how far can u shoot them?