Ever put a tightly filled balloon in the freezer, then come back and see it largely shrunken? Once you bring it back out into a warm room it expands again. Now what if we could use that expanding and contracting for moving a piston... and you've got the general idea. If you heat the air, it expands, if you cool it it contracts. It's a very simple idea, for a very simple engine.
let's get building!
here' s the video of the build and the engine working!
Step 1: Materials
plyers (long nose)
drill bits 1/16, 5/32, 1/2-3/4
CD and case / large plastic jar lid
10x5 inch piece of steel or aluminum two 5x5 pieces are fine, needs to have some thickness
CD tower (or even better) a LARGE 5 inch wide glass bottle. (see picture)
EPOXY (JB weld/ JB kwik AND regular, cheap epoxy. If it says non shrink, don't get it!)
*there's been a lot of issue with epoxy, I never realized different epoxies would cause such a difference, so I've added a picture of the epoxy. Here's one place to buy it: www.amainhobbies.com/product_info.php/products_id/37084/n/Bob-Smith-Industries-MID-CURE-15-Minute-Epoxy-9oz Hopefully this clears up the issues!
wire (welding rod is preferred, Stainless steel is best) 1/16 inch stainless or 1/8 steel - MUST BE SMOOTH and straight!
7 inches of PVC pipe
Foam board (5x10 inches or more, two 5x5 pieces are fine)
3/4" copper pipe
hotglue and glue gun