I have a vague memory of making one of these when I was younger and I've been wanting to recreate it for months. I just needed a can opener for the vents, some wax and an excuse to do it. Having acquired the formerly absent tools, this blog has provided the excuse.
1. Cut a door on an empty #10 can. I used Cutco scissors. (Bryce was so proud--both of me and the scissors).
2. Punch vents in the back of the can with a can opener.
3. Cut cardboard to the height of tuna cans. Roll the cardboard and fill the cans.
4. Place wicks in between the cardboard near the center of the cans.
4. Melt some wax. I did this in the microwave. The wax is sometimes available in the grocery store with the canning supplies. Wax used to be used to cover jams and jellies. While such a technique is no longer recommended, you can still get the wax next to your pectin.
5. Fill the tuna cans with wax.
There go you go. I can't wait to try this. It seems a pretty cheap fuel source for cooking, especially for cloudy days when a solar oven is not an option. I read one website that said you can use a tuna can as a cake pan and an additional #10 can on top to make an oven. I will be sure to post the results.