A video of the airgun can be found here: http://www.youtube.com/watch?v=WGaR2vzxUu8
I had a lot of difficulty getting the video to embed properly, even though I have not before. If anyone has a tip, let me know!
Webster's Definition of "piston": a sliding piece moved by or moving against fluid pressure which usually consists of a short cylindrical body fitting within a cylindrical chamber or vessel along which it moves back and forth
See source here: http://www.merriam-webster.com/dictionary/piston
Here's an overview of what will be explained in the following steps:
- Step 1: Materials Needed
- Step 2: The Build: The Secret to the Perfect Piston
- Step 3: The Build: Piston Pictures
- Step 4: Simple Airgun Theory of Operation
- Step 5: The Build: Simple Airgun
- Step 6: Conclusion
Step 1: Needed Materials
- PVC Pipe - (pic 1) - You can use whatever diameter you would like. In this project, I use a length of 1" Inner Diameter Schedule 40 PVC for the outer part of the piston. For the inner piece that seals against the 1" pipe, I used 1/2" Inner Diameter Schedule 40 PVC. PVC pipe is available at any big box home improvement store.
- Foam Rubber Sheet - (pic 2) - I bought this sheet at my local craft store. It is very cheap, and comes in a variety of colors and thicknesses. In this Instructable I am using black "Foamies" brand sheets that are 3mm in thickness.
- Hot Glue Gun - (pic 3) - Everyone has to have one
- Dremel or Rotary Tool - (pic 4) - I use my Dremel for nearly every project. Optional, but very helpful.
- Hacksaw - (not pictured) - I used this to cut the handles for the airgun I used the piston for. Optional.