How to Make a Fire Piston

This is an easy way to make a fire piston. A fire piston is a method of creating a fire by compressing air, causing heat, and igniting some tinder! More info on the fire piston.

DISCLAIMER:

I AM NOT RESPONSIBLE FOR ANY ACCIDENTS CAUSED OR RELATED TO THIS INSTRUCTABLE.

Step 1: Materials

Supplies needed for the fire piston:

1 Bolt 4'' x 1/2''

1 Hex cap 3/8''

1 O-Ring 1/2'' x 5/16'' x 3/32''

1 Steel pipe nipple 3/8'' x 3''

Some J-B Weld

Vaseline


Tools needed:

Grinder

Circular shaped files

Drill and drill bits (range of sizes from small to LARGE)

Oil

Awl and small hammer (optional, but helpful)

Large clamp

Q-tips

Dowel

Water and soap

Step 2: Checking Your Steel Pipe Nipple

In this step we are going to be looking at your steel pipe nipple. We are looking to see if your pipe has a bumpy ridge inside of it. If it does, go to step 3, if it doesn't, go to step 4.

Step 3: Getting Rid of the Ridge

To get rid of the ridge in the steel pipe nipple, take your file, and file it down! Now, this does take a while, so put on some tunes! :P After you are done, it should be smooth.

Step 4: Assembling the Chamber

To assemble the chamber, grab your J-B Weld, hex cap, and steel pipe nipple. Mix up just enough J-B Weld to fill the hex cap up about half way. Also, put some in the steel pipe nipple. Screw the steel pipe nipple onto the hex cap. Take your dowel and pack/tap the J-B Weld down in the chamber. After you have packed/tapped the J-B Weld down, set the chamber upright in a safe place for the night so it can dry.

Step 5: Grind the Piston

Now we are going to work on the piston. You are going to take the bolt and grind all of the threads down with the grinder. You want it ground to about 7/16 '' in diameter. Once you have all the threads flattened, (doesn't need to be completely smooth), make a notch in the bolt about 1/4"-1/2" of the way from the tip, just deep enough for the O-Ring to sit in snugly, but small enough to fit in the chamber. What I did was I started the notch with the grinder, but then finished it with the file. I would strongly suggest using the file unless you are skilled with a grinder.

While I was making the notch, every once and a while, I would slide the O-ring onto the bolt into the notch and test it in the chamber to see if it would fit yet.

After finishing the notch, I suggest filing down the rest of the bolt to get rid of any burs or pokey things.

Take the O-ring off after you are done.

Step 6: Finishing the Chamber

Once the J-B Weld in the chamber is dry, take your file and file the edge down where the opening of the chamber is.

Step 7: Drill a Hole in the Piston

Now we are going to drill a hole in the piston to hold the fuel (char cloth, paper, string, etc.). Start by placing the bolt into the clamp. Next, take your awl, put it in the center of the bolt, and hammer it lightly with your small hammer a couple times to get a small dent in it. This will help when drilling to keep the drill bit from sliding all over the place. Now, take your drill, and put your smallest drill bit in it, and drill a hole about 1/4" deep. Once this is done, move on to a bigger size drill bit, and drill into the smaller hole. CAREFUL, the advancement in bit size might grab at the bolt. To avoid this, push slowly down on the drill. Continue drilling holes increasingly bigger. When you get to around 3/32 size bit, or start seeing smoke, put a couple drops of oil in the hole, or enough to fill the hole. Continue to add oil in between drill bit changes, or when it starts smoking.

Step 8: Finishing the Piston

To finish the piston, squirt some soap onto the bolt, and rinse it under hot water. Next, take the Q-Tip, and wipe out the inside of the hole you just drilled in the last step. After that, take the O-Ring and stretch it onto the the bolt(piston).

Step 9: Grease the O-Ring

Take some petroleum jelly(Vaseline), or some other type of lubricant, and spread some on the O-Ring with your finger. Once greased, put it in the chamber, and push it in and out a couple times to spread the lubricant throughout the chamber. You should feel resistance, but the piston should be able to glide smoothlythrough the chamber. You may need to add additional lubricant to the O-ring because the grease will spread through the chamber.

Step 10: FINISHED! :D

Now you are done! :D

How to use your new fire piston!

Put some fuel in the hole at the end of the bolt/piston, such as char-cloth, paper, dry grass, etc. Put the bolt in the chamber, and set the chamber on something solid. Push quickly but hard on the piston. When you push on the piston, you want to compress the air in the chamber as much as possible. Remember to remove the bolt quickly after slamming the piston into the chamber, otherwise the tinder will smother and die. There you go! You have just made a spark with the fire piston! If you didn't get it the first time, blow in the chamber to get fresh air in it like you blow in a bottle to make a sound, and try again. Once you get your spark, you want to help it along with some more tinder, or maybe a cotton ball. All you want to do is to get that spark to transfer its heat to something else to make a fire.

I hope you had a fun time with my instructable! :D

Comments

[KevinC4]

the pic of you holding the screw to the grinder had me imagine the threads slicing into your hand shouldn't you have some sort of gloves on or is this scenario not possible I kind of want to know now.

[salomon1996]

I guess I didn't have a problem, as far as I remember... Gloves would be a good extra safety measure though! :D

[dwalden5]

For safety sake please do not wear gloves while using a bench grinder. Hold the item with some sort of clamp/vice grips etc. if it is too small to safely hold by hand. Look up de-gloving sometime to see what I mean. PSA over lol.

This is a slick little tool btw, once you get the hang of it it works great.

[salomon1996]

Thanks for correcting me! Always good to learn how to properly use equipment. :)

[Morpheus]

This is awesome! I made one and it worked first time! The only changes I made were using a much longer bolt with a short thread. I cut the threaded end off, and didn't have to worry about filling the threads. I followed all the rest of the instructions as listed (I did use a silicone o-ring). A great 'ible, even two years on...

[salomon1996]

Thanks for sharing, and nice improvement on it too!

[nkz75]

I understand the working principle for this.

Are you able to compress the air hard enough so you can reach really high temperatures? Looks a bit optimist to say the least.

Thanks for the instructable!

[salomon1996]

It may look optimistic, but it is possible! May take a few tries, but you can get it!

Thanks! :)

[fetech]

Have you thought of using an appropriate sized eye bolt instead of a carriage bolt?

[cameron and blake]

awesome

[salomon1996]

I guess I would prefer the Carriage Bolt. You could sure try an eye bolt, but wouldn't the eye be in the way? Interesting to try though.

[fetech]

My thought was that one could get a better retraction pull by using the eye of the bolt. Just mental attempt at a better mouse trap.

[salomon1996]

True, maybe one could just somehow make it more comfortable to push downward.

[mikaleda]

you could use a lower grade bolt and it would be easier to drill it doesn't need to be a super hard bolt

[salomon1996]

True.

[godoggie]

One thing to keep in mind is that the petroleum jelly will eat away at the O-ring with time. Since this is simple to take apart, it would not be hard to replace, so it's ok. Good 'ible!

[salomon1996]

Thanks much! :D

[chefpatrick13]

did not work. AT ALL.

[masterbuilder]

Why did you need to use J-B weld for this? Why can't you just screw on the cap, or maybe use a bit of gorilla glue/pipe dope to get it completely airtight?

[salomon1996]

Gorilla glue or pipe dope would most likely also work, J-B Weld was just what I used.