In my country it was called prespan , it had ugly smell when burned. Fortunately it is not produced any more.
From wikipedia:
Adequate ventilation or respiration protection are mandatory during high-speed machining, as it gives off toxic vapors.
Stay safe!
Adequate ventilation or respiration protection are mandatory during high-speed machining, as it gives off toxic vapors.
Stay safe!
In true DIY fashion you could make the genuine stuff yourself, by soaking or painting cardboard with epoxy or gorilla glue or similar. I think that would be FR1, minus the fire retardancy of course. If you want to get fancy, use layers from an old cotton T-shirt + resin: voila, home-made FR2! For extra nice surface finish, wait until the missus is running an errand, and give it a quick press with the clothing iron!
If you can't find FR4 (or FR5), then G-10 will also do, and will be a bit sturdier than the paper or cotton based products. It comes in a lot of thicknesses, even in blocks. Machining is a bit iffy because of the embedded glass fibers, so eye protection and a mask for breathing is probably a good idea.
If you can't find FR4 (or FR5), then G-10 will also do, and will be a bit sturdier than the paper or cotton based products. It comes in a lot of thicknesses, even in blocks. Machining is a bit iffy because of the embedded glass fibers, so eye protection and a mask for breathing is probably a good idea.
Both FR-1 and FR-2 are paper and phenolic resin based.
FR-3 is paper and epoxy resin, FR-4 is fiberglass cloth and epoxy resin.
Replacement terminal strips are still sold.
https://www.dynakitparts.com/shop/terminal-strips-original/
I guess it depends on what's the owner trying to achieve - to modernize the amp or to keep its historical value