Penny stoves are usually built from two soda cans and they look like this,
with some variations between the builder and so on. The basic idea is you have the bottoms of two soda cans stuck together with one inside the other.
The problem I have always had is that when I go to put the cans together, it is hard to do so without having one of them split and then you have to start over.
When building a penny stove, how can I keep the cans from splitting?