fire from a 2AA Mag

Finally a use for all those 2AA mags that are sitting aroundoo:
for detailed instructions go here
http://wiki.goingprepared.com/index.php?title=MagLite_fire_piston

sorry I dont know how to imbed the video directly so heres the link to the video of it in action
http://www.youtube.com/v/-djD2n2YSv0"

A fire piston out of a Minimag... never thought of that. It's a good idea, though, taking advantage of the small size and sturdy construction.

Interesting. I never knew the fire piston existed.

I have been thinking of making a fire piston. Maybe now is the time. Thanks.

nice find. looks like a good thing to take on long camping trips if you dont wana carry a lighter or the gas runs out.

How does a fire piston work? I am intrigued.

oh b@rt...

The air in the piston is compressed like a diesel engine. The air gets hot and lights the tinder inside the tube.
I hope this helps.

pretty neat..but wouldnt it be a lot easier to carry a lighter :thinking:

yeah, but whats the fun in that?:laughing:

I dont use fire pistons...I prefer chemical fires
magnesium shavings for now, negative X later

kts said:

pretty neat..but wouldnt it be a lot easier to carry a lighter :thinking:

Click to expand...

I'm the one that made the video and will be the first to admit that it is completely impractical. You can fit several much more effective fire starters in the space that this would take up. I would never carry this on a trip where weight or space mattered. Come on though, pushing down on a MagLite and making fire? That's just fun.

More info here.

That's cool! I may have to make one.

As far as being practical goes, this does give me an idea for yet another use for old MiniMags...how about taking the guts out and just storing matches and some kind of dry tinder in there? In that case, the stock o-rings should be enough to keep the contents dry, even if it gets dunked and you have a fairly reliable way to start a fire without using up too much space. :shrug:

I really like the fire piston idea though...I foresee some wagering where I work. I can see it now..."I bet you ten bucks that I can start a fire with a simple MiniMag..."

Great idea!!! :thumbsup:

Well, they are surprisingly not watertight. That was the first roadblock that I came across. If you decide to use them as dry storage, make sure you use a liberal amount of teflon tape on the threads to keep them sealed.

lumiphile said:

Well, they are surprisingly not watertight. That was the first roadblock that I came across. If you decide to use them as dry storage, make sure you use a liberal amount of teflon tape on the threads to keep them sealed.

Click to expand...

You were trying to build as high a compression rate as possible inside the light though...that's vastly more pressure on the o-rings than you would get from a simple dunk in a couple of feet of water. I'm sure that once you get deep enough though, maybe 10 feet or so(?) and the stock seals would not be enough to keep water out.

I wash my MiniMag in a sink under full water pressure with hand soap a few times a week due to the various nasty things it gets exposed to in the normal course of my job and have done so for years with several MMs and have never found moisture inside one of them. I have dunked them in various shallow depths countless times over the last couple of decades never finding moisture inside the light. Of course, I have always kept the o-rings well lubed with silicone grease (or various other lubricants over the years), which I'm sure helps with water resistance, but would be of little value against the high pressures built up inside your fire piston.

I would think that for simple water resistant storage, unless you plan on going diving in fairly deep water, a MM with well lubed o-rings would do a pretty good job...of course, teflon tape definitely wouldn't hurt and may even prove useful for other things in a survival setting. :shrug:

The gasket in (modern) Mini Maglite and Solitaire tailcaps is designed as a one-way valve. It's supposed to keep external pressure out (for water resistance) but allow internal overpressure to escape. That's why the tailcap gasket is NOT an o-ring.

Anthony Maglica, in U.S. Patent 6,361,183, for example (he has a LOT of patents) describes a number of ways to make one-way valves. Buried in this patent it says...
"However, in infrequent occurrences, pressure has built up in such devices. This is believed to be the result of outgassing from a defective battery."

This URL gets you to the patent, if you like tedious descriptions...
http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=6361183.PN.&OS=PN/6361183&RS=PN/6361183

But Maglites can't always relieve pressure fast enough. "Vent-with-flame" battery incidents produce too much pressure too fast, and something else in the flashlight has to open.

That's true...I wasn't very accurate in describing the tailcap seal as being an o-ring. Seems like my 25 yr. old MMs had o-rings, but I may be mistaken about that...might have to look for them and see if they use the same beveled seal as the newer ones do. I have no idea where one of them may be around here, but I'll have to keep my eyes open.