It is old news that you can print PCB artwork on glossy paper and use a clothes iron to transfer the toner to a copper board, which will resist etchant. But [Squalius] shows us how to do a similar ...

Objectives: This study aimed to evaluate the effectiveness of urushiol as an additive to surface acid etchant on dentin structure, by assessing the biostability of dentin, and determine the bonding ...

We also like his use of an Erlenmeyer flask and a torch to heat the etchant. We don’t make PCBs in the winter because our Cupric Chloride is too cold to use outside but that may change now.