Fire Piston Prototype

[Nate Davey]

I've wanted to try an fire piston for some time, so while waiting on some roughed out hollow forms to dry, thought this would be a good time. For those of you not familiar with a fire piston, it works on the same principle as a diesel engine. Use compression to start a fire. The fire piston itself is several hundred years old and, obviously, predates matches. The original piston were made entirely of wood. I opted for brass pipe and an aluminum piston. It works, but I need to make some char clothe to get a good ember. Dryer lint smelled burnt, but no ember. In my minds eye I designed it to be screwed shut when not in use, but he O-ring, doing it's job, holds the air in the bottom so it wont close the whole way. Walnut and brass, sanded to 300 starting to put on oil coats. Still need to sort out the brass end but wanted to see if it is doable. Additionally, I wanted to us a brass cap, but the borg didn't have the right sized cap so had to opt for an 1/8 to 1/4 adapter and 1/4 plug. Candid criticism and advice greatly appreciated.

 

[Elmojo]

Looks really nice Nate!
I tried making one a while back, and to be honest it never worked right.
The only thing about yours that I think you might want to change is the brass bottom fitting.
The fire piston is often used between 2 hands, and that square brass fitting might be a bit rough on the palms.
You may be able to turn a small knob or mushroom shape to cover the brass part. That would protect your hand and still show off the beautiful brass and wood contrast.
Other than that, it looks awesome!
I'm looking forward to seeing it complete. Maybe then I can see what I did wrong and make one that works. I think my father would enjoy having one.
-Mike

EDIT: Upon re-reading your post, I see that you already have plans to refine the brass cap. Ignore my suggestion, other than maybe the idea of the hand protection factor.

 

[Glennbear]

Very cool Nate, I do not have any construction suggestions however I do have a theory as to why the dryer lint did not work. Cotton fibers ignite well but a lot of our modern clothing are man made materials with different ignition temperatures ergo burning but no ember. You might consider fibers pulled from a cotton ball in the bathroom cabinet.:wsmile:

 

[Sealeveler]

Nice project there.Might have to try one.I have one my father made when he was a Scout Master.
Tony

 

[CaptnA]

Once you get it, they are a lot of fun to make.
If you don't know how to make char cloth, let me know.
It is very simple.
What is the depth tolerance? It has to be JUST deep enough, but not too deep
or you'll never get enough compression to ignite the char cloth. You can fudge more on piston diameter
than on depth.
Keep going, they are a hoot!

 

[Glennbear]

Once you get it, they are a lot of fun to make.
If you don't know how to make char cloth, let me know.
It is very simple.
What is the depth tolerance? It has to be JUST deep enough, but not too deep
or you'll never get enough compression to ignite the char cloth. You can fudge more on piston diameter
than on depth.
Keep going, they are a hoot!

The simplest way to make char cloth is to turn me loose with a hot iron and a cotton shirt. :rotflm: