I use plain foundation. The vertical (crimped) wires are meant to be fixed by a piece of the top bar called a wedge. Itâ€™s a small cleat that is almost sawn off one side of the top bar.
My frames are used for both brood and extracting. I use 4 wires in my deep frames and 2 wires in mediums.
A 12 volt battery charger is all that's needed. Yes a car battery will work, too. The battery will have to be charged somehow.
If there is any interest, I will share the construction of my embedding board. It isn't any different than any other that I have seen except I couldn't find a couple of pieces of phosphor bronze, so I used cloths pin springs to make the contacts out of. You lay the frame with the foundation inserted in the slot in the top bar. Slide the frame against one contact, then push the other contact into the wire and watch the wax melt. When the wire moves into the wax, you release the contact, let it cool for a second, then do the next one.