big problem, mini gun

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<WOG>
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Sat Nov 24, 2007 12:11 am

can anyone help me??

im pretty new and i don't understand mini guns too well. i can NEVER get the right amount of fuel in it so it rarely fires. do you need the exact right mixture of fuel and air??
or is it maybe the fuel itself??
i use axe as fuel and it works...sometimes.
and i can see inside the chamber that the peizo makes a spark every time.



thanks in advance
,
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TheTrooper
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Sat Nov 24, 2007 12:23 am

Well WOG, can you get a picture of the mini it would help a lot of people figure out whats wrong and try spraying a little in and waving the chamber around (not to much) to kinda air it out. That way the fuel isn't to saturated in the tank
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SpudUke5
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Sat Nov 24, 2007 12:27 am

Yes as trooper said, there is to much fuel. Its kindof hard to think that there can be too much fuel but there can. All you have to do is air it out a little. Dont spray too much into the chamber. Spray like a millisecond or something. If you get a good oxygen to fuel ratio by wafting it a little, then you should be able to fire it.
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mark.f
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Sat Nov 24, 2007 9:34 am

It's been suggested rather often lately, in threads right below yours, ( :wink: ), to simply use a syringe to inject a gaseous fuel. Pretty damn accurate, cheap, and simple.

If you use propane as a fuel, your injecting of fuel will displace air, so inject 4.03% of the chamber volume of fuel with the syringe.

If you use butane as a fuel, the same applies, so the ratio fuel:CV will still be adjusted to 3.13%, rather than the stoichiometric ratio.
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jimmy101
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Sun Nov 25, 2007 2:08 am

Like markflh11q said, a syringe is very handy, particularly for a mini.

You can get them at stores that sell horse, pig and cow supplies. Small ones sometimes come in inkjet cartridge refill kits.

Another way to go is to attach a small ID hose to a disposable butane lighter. Check you junk box for a piece of insulated wire with the right gauge. Just strip off a length of the insulation to use as the small ID hose. To measure the fuel you just count "0ne potatoe - two potatoe ...". Doesn't seem like it would be very accurate but it is much more accurate and reproducible than trying to spray into the chamber with an aerosol can.

Most butane lighters put out something like 1cc/second with the height control opened up all the way. Probably a bit too fast for fueling a mini, so set the flame height to the lowest possible setting.

Might want to take a look at this
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Zen///
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Sun Nov 25, 2007 2:31 am

at stores that sell horse, pig and cow supplies.
What a nice place you live in :D
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Redcoat
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Sun Nov 25, 2007 2:36 am

After spraying the fuel into the chamber, give it a light blow. And then wave it gently.

Should work, My friend called me with his exact problem and that's all it took.
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jimmy101
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Sun Nov 25, 2007 12:04 pm

Zen/// wrote:
at stores that sell horse, pig and cow supplies.
What a nice place you live in :D
Yep.

Actually, unless you live in the middle of a big city like NY or LA there should be a store "nearby" that has stuff for farm animals. Even in a yuppified area there are probably enough people with horses to support a farm supply store.
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Sun Nov 25, 2007 1:14 pm

I'd recommend something other than a horse syringe for mini fueling, though. :wink: Have you ever seen how big a horse syringe is? They've got em at the feed store where I live, along with medicine in a fridge I always mistake for the coke fridge. :P
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Mon Nov 26, 2007 12:48 pm

markfh11q wrote:I'd recommend something other than a horse syringe for mini fueling, though. :wink: Have you ever seen how big a horse syringe is? They've got em at the feed store where I live, along with medicine in a fridge I always mistake for the coke fridge. :P
Ya, you're right. Horse syringes are typically 60cc or so. A mini probably only needs a single cc or so. The store should have smaller syringes for smaller animals. A 5 or 10cc would be good. Get a couple blunt tip syringe needles as well. Syringes are usually less than $1 and a couple needles ~1$.
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