What is up eveybody, in this instructable I am going to make a mini fire piston used for lighting a fire with an air combustion.
Hope you enjoy it.
Step 1: 3d Design
I firstly design a piston in software called solidworks to see how it is going to look like when machined.
After the first prototype, I had to change a few small dimensions and it was ready to be machined.
Step 2: Material, Machining First Part
For this project you only gonna need a 20mm in diam. Aluminum rod and 2x 7 mm rubber oi-ring seals.
The piston is made from 3 seperate parts so I fistly cut them on length with my handsaw.
I start with making the middle part of the piston, so I trim down the diameter to 15 mm and drill 10mm hole through the whole piece.
On one end I tap a thread so we could seal it with a custom made cap end.
Step 3: Machining Remaining Parts
Second part is kind of a piston with a seal on one side. Again, I trim most of the rod to a 9mm diameter, made some grooves and 2 lite chamfers on both sides.
The last part is just a simple cap end with a thread on one end, so I firstly trim it down to a needed diameter and cut an external threat in the benchwise.
After that I hold it secure again in my lathe and machine it to the final dimensions. In the middle section I also cut a few grooves to kinda look a bit better. After that I drill a small hole in the cap end for the rope that we are gonna attach at the end and make a little groove on one end of the piston for the charcloth to hold in tight.
Step 4: Assembly and Testing
Now, our fire piston can be assembled together in just a few seconds and there we have it.
To test it out I use a small piece of a charcloth which is a very good fire starter and place it at the tip of the piston.
With a hard push we can achieve a very high pressure that helps ignite the charcloth.
You might not get it started every time but after a few tryes you will figure it out how to trigger it almost every time.
Thank you for reading that quick instructable, if you have any questions or improvement ideas please comment below.