mini combustion gun, not working

[cannon]

right, i have attempted a mini combustion gun and it is not igniting, there is a spark but no umph from the chambre, it doesnt fire or anything just dead as it is my first time making a gun and i only used simple items im not sure if i have done it correct but i have seen it done with the same items, there is a pic below of what it lookes like is there any advice you could give me


http://photobucket.com/albums/v735/bass ... 337c1e.bmp

the items i used were :

paracetomol bottle
clicker from a lighter
tape
ben casing cut down
there is also a paper clip inside so the spark can jump

thanks

cannon

[spudshot]

too much fuel, also, are you venting your chamber between attempted fires?

[cannon]

yea i take the ammo out and then blow through the pipe making sure it all gets clear then start again, im currently using hairspray and a screwed up rizla, any reccomendations?

[iamthewalrus]

u prolly are flooding it, minis are really really hard to get the right mix with

[cannon]

so how much or how long do i spray? also would it be a good idea to use a bottle like this?, but without the nail varnish remover in it lol

http://www.remployht.co.uk/media/images ... 250_sm.jpg

[iamthewalrus]

u should put the very least u can in, spray the smallest amount possible, even then u might be flooding it, so try spraying from different distances.

[spudshot]

i've heard that nail polish remover can harm some plastics, i use a small spritzer bottle of cologne, it works fine, one spray and it always fires

[cannon]

now im using a pop bottle and made a trigger box because the first time i tried it the bottle blew apart so now im fireing from a distance, seems to work ok, just need to seal the holes where the wires go in for the spark

Pics coming soon

[drac]

http://minipillbottlegun.mypicgallery.com/
I use about 4 seconds from a propane torch to fill it. The time varies with the fuel you use.

[cannon]

changed my mind about what im using now, im using abit of drainpipe lol and its been working fine for a while now and i started to up the gas and now its blowing the end cap off and i cant seem to hold it on properly. i am using a very strong glue but so far it is not working any ideas what to do?

[iamthewalrus]

i would highly suggest not talking about stealing pipes or anything else in this form, its illegal which breaks a forum rule.

[spudshot]

yeah the forum popo might come after ya anyway, if you're using some other glue than PVC primer and cement to hold your cannon together (i'm assuming it is pvc, if not disreguard that last statement) then i suggest you not use the cannon anymore, the cap shouldnt fly off if its screwed on far enough, check the threads to see if the molding marks are protruding into the threads (that would stop the cap from going on farther) if they are take a fine file and file the marks away

[boilingleadbath]

I'm not sure, but it's more expensive than right gaurd (which is the recomended fuel). If I remember right, it's 'active' ingredients are largely alcohols and florohydrocarbons. Probably not as effective as the propane and butane [isomers] in right gaurd.
As far as aerosol fuels go, right gaurd (brown can) is the recomended fuel.