Just my observation and it may just be my cap maker.
The picture shows 2 caps. The one on the right is the typical soda can. The one on the left is from an aluminum baking pan
The baking pan produces a more uniform cap with a clear visible round bottom. The soda can material is not as defined..Although the soda can material works just fine, I am going to start using the baking pans. I have also tried the brass sheets but it is not as readily available like the Dollar General stores on every corner for the baking pans.
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