In this instructable I will attempt to show you how to make a fire piston using relatively common materials found at your local hardware store. It took me a few attempts to get it working right so hopefully this instructable will help you benefit from what I've learned. The cost is under $20 per piston though some of the suplies like brass rod only come in 4ft sections so I'm dividing the cost down for each individual unit.
What's a fire piston anyway?
A fire piston is an amazing little tool that's been around for hundreds of years, unfortunately due to the invention of the common match its popularity diminished and it almost dissapeared. It is a piston and cylinder that works like a diesel engine using compression to cause a piece of tinder to heat up rapidly and turn into a coal. Wikipedia explains it better than I do so if you're really interested just click here
for the full history.
The most important part about getting one of these working seems to be the char cloth or char string which is used as the tinder, don't be fooled by other videos online its almost impossible to light just regular balls of rolled up tissue paper. Charcloth
is a cotton based material that is heated in an oxygen deprived container until certain gases etc are released afterwhich the remaining material turns to an ember really easily. Another characteristic of char cloth is that the ember grows when it is blown on (so wind actually helps you!)
Making a fire piston without having char cloth will make you go crazy, chances are you'll have a working piston but won't know it because your using the wrong tinder. Make char cloth first!!!
5" or more of 1/4" brass rod
4" 1/8th Threaded brass pipe nipple
1/8 Threaded brass cap
1/4" OD 1/8" ID 1/16 Cross section rubber o-rings aka -006 size
2 part liquid epoxy (Jb Weld, Cold Weld etc)
Wooden cabinet knob (or you can make your own)
Wooden Broom Handle or suitable wood for turning*
Cotton T-Shirt (Optional for making char cloth)
Tin can that seals (Optional for making char cloth)
Drill Press & Drill Bits
*Not all the tools/materials are necessary just to get a working piston. Instead of using a lathe you could file the o-ring groove by hand for example. The wooden sleeve made from the broom handle is optional as its purely cosmetic.
**All the slides were made with Google Sketchup, playing around with the styles gave it the illustrated look and it reminded me of a kids book so I ran with it ;)