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Mini Spud Gun, Classroom Nemesis

Step 7Why doesnt my spud gun fire?

For the ones who simply dont have the effort to spare looking at problems users often experience while making, operating, or modifying the miniature spud gun and the intricate and detailed answers I provide with meticulous attention paid to a legible, understandable, and accurate solution or suggestion to all of the inquiries and enigmas Im intelligent enough to answer or at least the slightest of effort.

Problem:
You loaded a projectile that fit right, filled the chamber with a good propellant, sealed the chamber, and hit the igniter but the propellant doesnt ignite and nothing has exited the barrel but can see a spark leap across from one wire to the other when you squeeze the igniter:

Answer:
You put too much propellant in the chamber resulting in a fuel content too rich and dense to ignite by ghetto means. Depending on the propellant, chamber, and other small, meticulous variables the air fuel ratio has to be ideal to be able to ignite. Its hard to measure the propellant content by any reasonable means so the remedy given is not a sure-fire thing but with practice the process can be somewhat reliable. Spray a small amount of propellant in the chamber, use your reasoning abilities on determining how much is a small amount and if it fails experiment logically knowing that if you spray for X-milliseconds/amount-of-time (you dont need to keep track) and if it doesnt ignite, purge the chamber by blowing through the chamber (unloaded, no projectile) with a moderate amount of force until satisfied and sure enough that there is no gas in the chamber that can alter the series of trials and errors (unless youve found the divine method) and spray again with an amount a little less propellant and repeat until successful. Ive experienced the best performance by quickly pressing the spray button all the way down and immediately releasing it and then gently blow into the chamber. It takes a few tries until you get it right but its the best way I know how.

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25 comments

Jan 19, 2008. 3:14 PMDELETED_craz meanman says:

(removed by author or community request)

Jan 28, 2008. 9:09 PMLuxordo5 says:

lol, make sure the chapstick you're using is the one with a screw cap. I made one with a glue stick container and it backfired me with a humongous bang. I learned to use a glustick with a screw cap, but instead I just put together a water bottle head with it and works fantastic. Just tell me if you want to see a picture of it.

Aug 30, 2009. 8:53 AMgeodez says:

just make it fire the lid.

Aug 7, 2009. 4:04 AMNIJU! says:

i made a mini glue stick one which used a 8g glue stick the lid has only ever blown of once which scared me but didn't hurt. now i put my thumb on the lid (: