Fuel mixing?

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Postby Iowaengineer » Tue Feb 06, 2007 9:28 pm

Just testing out my new gun AKA Chucky, I have found that a mix of axe and lighter fluid is a very powerful combo. Are there any other combos that you have tested that work?
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Postby FLONE » Wed Feb 07, 2007 9:49 am

Static Guard or OUST using the nozzle from a can of Static Guard. Tried the lighter fluid once, horrible stench! Currently I'm using a 32 oz Rubbermaid Heavy Duty spray bottle with adjustable nozzle. Mix 1 bottler red HEET, 1 bottle yellow HEET. Adjust the spray to reach 1/2 way into the chamber, followed with a second or 2 of Static or Oust. I read a lot of posts on starting fluid, still winter here, a new idea for spring.
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Postby jimmy » Wed Feb 07, 2007 11:24 am

I doubt there is a significance difference in the actual energy in any of the fuels used in spud guns. With the <u>proper fuel ratio and proper mixing</u> all common fuels will behave about the same. It would take a chrony to tell the difference.

If your fueling method is "squirt and screw" then the power of your gun is based on how accurately, and consistently, you can do that. Not on any difference in the amount of energy in the fuel.
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Postby FLONE » Wed Feb 07, 2007 3:30 pm

<blockquote id="quote"><font size="1" face="tahoma,verdana,arial" id="quote">quote:<hr height="1" noshade id="quote">Originally posted by jimmy
[br]I doubt there is a significance difference in the actual energy in any of the fuels used in spud guns. With the <u>proper fuel ratio and proper mixing</u> all common fuels will behave about the same. It would take a chrony to tell the difference.

If your fueling method is "squirt and screw" then the power of your gun is based on how accurately, and consistently, you can do that. Not on any difference in the amount of energy in the fuel.
<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">
Probably not in the aerosols, thought that propane or mapp had the most energy?
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Postby mafia_mike » Wed Feb 07, 2007 7:18 pm

what i do is that i look on the label of the can and most of the time (im guessing of not all the time) the ingredients that are listed first it will have more of (like powerade's main ingredient is water) SO with that, if propane is higher on the list if not first then go for it
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Postby jimmy » Wed Feb 07, 2007 8:19 pm

Mafia_mike is right.

Since most aerosols use propane as the propellant,
(well most aerosols that work in a combustion gun anyway),
and the "active ingredient" (deodorant, paint, clear lacquer for hair ...)
    is a relatively minor component (which may or may not burn),
therefore most aerosol cans are roughly equivalent to using propane.

The difference between butane, propane, MAPP etc. is really pretty minimal.

You see lots of post about one fuel being better than another but there is little actual data to back most of those up. More often than not the "reported difference" is due more to differences in the volatility of the fuel, and how well it mixes with air, than to the energy it actually contains.

The only solid data I know of is Latke's <a href="http://www.burntlatke.com/lpmapprussets.html">Propane versus MAPP</a> comparison. MAPP gave muzzle velocities about 10% higher than propane. 10% is significant but not a huge change.

When someone says something like "I have found that a mix of axe and lighter fluid is a very powerful combo" mostly what they are observing is that they have crappy fueling and mixing procedures and those procedures are "least crappy" with that particular fuel.

Not trying to rag on ya Iowaengeneer, but if you go to a meter system and mixing fan I suspect you'll find your gun performs much better, and it won't really matter what fuel you use.
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Postby Iowaengineer » Fri Feb 09, 2007 9:18 pm

gotcha. The integrated fan will be on my next project (in the works right now) and will be finishing it this weekend.
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