40 years ago my husband and me did a lot of enameling, very tiny   pieces  less than one inch, with conteremail, we fired  the  2 sides together in  1 firing. My husband cut  3 points trivets in tops   and backs of cans. Nowadays most of cans are painted inside and I don't know the way  it would work. They went  through many firings and were easy to replace . When I got my material from the attics I found  them. I'll make some pictures for you

WOW! What a great idea Francoise - I never thought of using cans - did they shed any fire scale?

Most cans are not painted inside, especially for food - i will cut out some and try these out - I would very much like to see photos of yours.

Thanks a lot!

Trish