butane vs propane

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imjustpk
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Fri Feb 09, 2007 1:39 am

so who uses butane or propane in the combustion guns and how well do the two work? also are they more powerful than say when you use axe or another spray?
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chaos
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Fri Feb 09, 2007 5:50 am

yer well i use butane in mine its hard to get the mixture right sometimes but other than that its more powerful than deodorant

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MrCrowley
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Fri Feb 09, 2007 6:31 am

imjustpk wrote:so who uses butane or propane in the combustion guns and how well do the two work? also are they more powerful than say when you use axe or another spray?
Search 'Propane' under 'Combustion Cannon Showcase' and tell me how many matches you get. Loads of people use propane/MAPP very few use butane.
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chaos
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Fri Feb 09, 2007 9:27 am

while on this topic does ne1 kno how to measure butane aerosol cans?
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Hotwired
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Fri Feb 09, 2007 9:34 am

The larger the hydrocarbon molecule the more energy that is released when it is burnt.

Butane (C4H10) > Propane (C3H8)

Both are better than a hairspray or similar aerosol.
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jrrdw
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Fri Feb 09, 2007 9:37 am

Ever think about mixing the two? Or would that be a bad chemical reaction?
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Hotwired
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Fri Feb 09, 2007 9:41 am

You've never seen camping gas?

Its a butane/propane mix in a 60/40 or 70/30 ratio. If you wanted to use it you just need to make sure you have the right air mix after taking into consideration that its not just one gas.
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jrrdw
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Fri Feb 09, 2007 9:53 am

Hotwired wrote:You've never seen camping gas?
Yea, i've seen it but never knew what it was made of, learn something new everyday.
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chaos
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Fri Feb 09, 2007 10:03 am

you can buy it as a pure gas tho its for refilling lighters i got some 9bucks a can still i would like to know how to meter it.

peace
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willarddaniels
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Sat Feb 10, 2007 12:37 am

I use metered propane.
I suppose to meter white gas/camping gas you would need to know how much volume of air the evaporated gas takes up. Your combustion will only use that amount of camping gas that has evaporated. Hence, too much is not good, you just waste it. This is the reason that propane and mapp are very popular, their liquified state is at a higher psi: 90-110. This makes it easy to meter and get more precise results.
Bottom line, experiment with it. Use an eye dropper to measure the amount of white gas you put in each time and compare results using muzzle velocity or simple "hang time". Use the same control ballista each time. Make sure that you either use a chamber fan to help in evaporating / mixing the fumes or wait until it has all evaporated.
Mic Whitey
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Mon Feb 12, 2007 5:20 pm

butane is much better than propane. it's not hard to get the mixture right at all. I made tool that gives me control to give two shots of butane for 4" gun and 3", so ha
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willarddaniels
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Mon Feb 12, 2007 11:37 pm

Interesting, Mic Whitey. Can you elaborate a bit on your "tool"? How does this tool give you two shots for both a 4" and 3" chamber? Do you meter it out for 2 separate shots? I am a bit confused in trying to visualize this. Perhaps you can enlighten us a bit more.
I'm sure imjstpk would be interested as well, since this tool of yours may be just what he is looking for.
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imjustpk
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Tue Feb 13, 2007 7:36 am

actually i am very interested in the idea of a butane metering device, perhaps it could give mapp and propane fans a run for their money
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chaos
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Tue Feb 13, 2007 7:56 am

Mic Whitey wrote:butane is much better than propane. it's not hard to get the mixture right at all. I made tool that gives me control to give two shots of butane for 4" gun and 3", so ha
mate please i beg you, i have spent hours in the shed "trying" to make something to measure it please post plans. i am sure if this works good many people will be help by this also
thanks mate.

peace
chaos
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BC Pneumatics
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Tue Feb 13, 2007 9:01 am

chaos, butane is packaged by weight, so it would be incredibly easy to find out how much is in it. all you have to do is look at the Can
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