SpudFiles

Hold on. I thought your vent was a shrader valve for use with a bike pump to pump air into the chamber. if its just an open port then yes sealing it off would give you a much better shot.

Even if the tape protects you from shards of pvc, i doubt it will protect you from the heat that may creep through between the piezo and the cap. This happened on a friends launcher and while firing it i nearly burned my hand.

after having a think about it and using spudtyrant's diagram,ive now rigged the piezzo into the drill handle,it works a treat now and is a lot safer,,


and about the port/vavle did u think it was a pnumatic cannon????,,putting the ignitor in the cap was scary,but pressuring dwv is fucking phsyco.....

ive attached some more pics of the new ignition...

hey Gaderelguitarist ive used ur idea of a sharder vavlve to refuel ,with hair sparay ,i pulled the centerpin/vavlve inards out so it can be refueled via the sharder valve,as u would with quick connect air fittings

works a treat

and the final product( i think)!!!! i added a bike pump to clear the chamber
of dodgy gases

Nice job the only thing i would have done was put the screws further back in the chamber.

You can just leave the current screws in and splice some wire and put new ones where you want them.

you want your screws at the screw cap fitting here http://img158.imageshack.us/img158/3077/newscrew.jpg
on your chamber for the best ignition.

You will get dodgy ignition with you current placement, gasses are heavier than air so if you firing up or at any kind of an angle most of them will drop to the bottom of the chamber and will have trouble igniting

I would say scrap the bike pump because it doesn't do to much to ven,t but it looks so cool lol

damm i nearly got it right lol, yeah i was looking for the thickest part to put the screws in ,and where i choose was three layers thick of plastic

ive dry fired the thing about 15 times and now i can realy appriciate y there called spray and prays

if u consider how i fire it (with the junction arm facing down)would it be more viable to put the screws in the lower arm????
im refuling with everything upright (the hairspray and the cannon)
via the shrder valve

the junction arm should work even better i would mount it on top of the top of the wye fitting going out to the juction arm where it is double layered.

as far as fueling goes i would just cover or plug the schrader and open the screw cap to fuel that has always worked best for me because the aerosol goes into the whole chamber and is not just shot to one wall.

Don't use hairspray it leaves a sticky gummy residue on the walls that can render the gun unuseable after a while and on top of that it smells bad. go to you local supermarket of any store that sells deoderant and read the back look for fuels such as butane and propane and sd-alchohol 40-b and the more of these ingredients it has the better fuel it will be

so u think now that the ignitor is out of the cap its safe to use butane???

im keen on it. its just im shit scared the thing will blow up,,,have u used butane in a basic 100mm dwv fitting before.......????

ive used propane in 4"(100mm) dwv before 100's of times out of a metered system which add the perfect amount for peak ignition and propane has a higher ignition pressure then butane as long as you added plenty of primer and glue there should be no problem using butane. if your really that scared of it exploding then you could always just make a new one.

after that answer im grabbin some butane tommorow,,,,how much of an improvement am i likly to see considering i can shoot a golf ball about 150meters using hair spray?

just another thort is it possible to get twin sparks off the one piezzo ignitor

will the spark be strong enuff?

FORE!!!! wrote:just another thort is it possible to get twin sparks off the one piezzo ignitor

will the spark be strong enuff?

it's possible and has been done but they have to be about 1mm gaps.

since this is your first i would just keep it simple and go more complex the more you learn at the moment i have 3 advance combustion about 10 pneumatics and 1 hybrid under my belt which pales in comparison to some people on this site.

just start off simple and add something different to each cannon you make i would just keep this one single gap there are too many problems associated with double gap piezo's there is always something you could improve on and as i have learned it is not for your first cannon unless you do a lLOT of research before making it.

Very nice!!

In honored to have my rough ideas used so well