Step 1: Auxiliary cylinder
The metal came from a old metal lid. Before use just scrape off all the plastic so as to not create toxic fumes when heated.
Step 2: The auxiliary piston
Note the piece of wire that has been embedded into the foil.
Step 3: Main cylinder
It was been made from a copper tube with another piece of copper soldered on to the bottom.
My soldering iron did not have the power to solder on to the large piece of copper so the joint is a bit dodgy...
Step 4: Main piston
Step 5: Crank shaft
Step 6: The Heat sink
I hammered the small tube in after drilling a small hole.