cannon wont work

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gijeses
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Sun Jan 01, 2006 9:38 pm

im getting a little spark, and ive been using starter fluid for propellant, btw this is a simple combustion chamber gun. i have a 10" 4" pvc combustion chamber, and a 36" long 2"pvc barrel. but its just not firing, the spark is pretty small, and im using a BBQ ignitor. can sum1 please help?
gijeses
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Sun Jan 01, 2006 10:39 pm

ok, im back, minus some eyebrows and 10 percent of my hair. damn thing decided to work AFTER i took off the end cap and was staring down the combustion chamber. and now its not working again. i replaced the plastic coated screws i was using with some thicker bolts, and im getting the same amount of spark and the same exact results : nada. can any1 help?
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Sun Jan 01, 2006 10:46 pm

Inconsistent ignition can be caused by using the gun in cold weather. The propellant condenses on the inside wall of the combustion chamber. Also to much or to little fuel can cause the same thing.

Why not fuel the gun with propane and a meter pipe, that way you can get consistent results.
gijeses
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Sun Jan 01, 2006 10:50 pm

propane? meter pipe?
gijeses
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Sun Jan 01, 2006 10:54 pm

im sorry, i think i forgot to say that this is my first cannon, and also, when i drop a match into the chamber it ignites
just not whenb i spark it, you think the spark may be 2 small?
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boilingleadbath
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Sun Jan 01, 2006 11:05 pm

Have you tried sparking it after taking the end off? (like in the attempt that failed to ignight it)
With starting fluid, it's very easy to put too much in the chamber - and if you do that, you get either a weak combustion or none at all.
gijeses
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Sun Jan 01, 2006 11:08 pm

yah, ive tried sparking with the end off, on, and every way i can think of, ive tried w/ just a little gas, a lot of gas, its not cold outside i live i FL for christs sake. and im trying to get this to work tonight. what do you think is the problem?
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Sun Jan 01, 2006 11:10 pm

(Number one) if the gun misfires don't use the sparker with the cap off unless you want to lose more eyebrows..... Air the gun out with the cap off before starting again.

How many second worth of either are you using? Start with only a very short burst in the chamber, as I suspect that you may be spraying to much.

There is a trouble shooting section here if you look around a bit.
gijeses
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Sun Jan 01, 2006 11:11 pm

also, ive never shot one of these before, can sum1 give me a detailed step by step on how to load the propellant? like spray for 5 secs then leave for 5 secs then cap? sumthing like that? rememver im using starter fluid
gijeses
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Sun Jan 01, 2006 11:16 pm

oh sorry, ive just been kinda cruising thru the site here, didnt see the trubleshooting section. how long of a spray shuld i do, then how long till i put on the cap?
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Sun Jan 01, 2006 11:17 pm

Read my instructions above, you are using to much either..... Start with a very small amount (1 second spray). More is not always better.....

Get the excess either out of the gun by airing it out first. You may have to use a rag if the chamber is already wet with either.
gijeses
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Sun Jan 01, 2006 11:22 pm

ok, ill go try, but what im asking is do i have to put the end cap on really quickly after i spray or let it air for a second?

(six minutes later)
kk, just tried ur advice, no go, didnt work with cap on or off. i sprayed for ecxactly one second then took about another second getting the cap on. did i do that right?
spudshot
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Mon Jan 02, 2006 12:34 pm

starting fluid is very hard to get a good mix, i just barely touch the nozzle and that little spray is enough for my cannon, just experiment, if it doesnt ignite take the cap off and let it air out for a while, then try again, it takes a while to get the mix right. oh and you can edit your posts, you dont need to double post
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CS
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Thu Jan 05, 2006 1:54 am

Another thing I have noticed about starting fluid is that you need to spray it in the center of the chamber. Because it will not work when it gets on the walls. This is because you want the fuel to be suspened (cant think of a better way to discribe it). As above I would suggest a dif fuel (AXE?). Good Luck. Ya you got that double post thing down (3 times).
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Atlantis
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Mon Jan 16, 2006 9:04 pm

Here's some advice when dealing with sparks.
1: Flame Facials are not fun.
2: The gun may fire even though it has been opened multiple times.
I have had both of these things happen to me, 1 was funny, 2 was not.
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