Electromagnet core sheath material

I am trying to think of a good material to use to wrap copper wire around an then slide the wire assembly onto a core. This sheath like (don't know what else to call it) material would help insulate the wire form the core and boost production speed. Anyone know of any real world examples or materials. Thanks guys as always.

One name for it is "fishpaper." See: https://www.mcmaster.com/#fishpaper/=klfr97

You might find the 0.010" about right. McMaster is given only to illustrate what it is like. Other grades and colors are available and probably at a much cheaper price.

John

You can also buy ready made bobbins in many different styles:
**broken link removed**

Thanks a lot guys, that should give me something to look over.

I was also wondering if bobbins for electromagnets reduce the strength of the electromagnet at all?