On Sat, 25 Oct 2008 04:21:20 -0700 (PDT), eric h
wrote:

On Oct 24, 9:21*am, "Karl Townsend"
wrote:
I need to make some new idler wheels for my wire EDM. The material is a very
hard black plastic. Maybe the same stuff you see on a car electrical
distributor. It needs to be non-conductive and be able to have a light press
fit for a ball bearing.

Can somebody give me a material name and source to order?

Karl

I sell various forms of plastic offcuts on ebay.

From what you and the others say, I would agree that white delrin or
phenolic is the way to go, but you could also have a look at unfilled
Nylon in the natural form. It's quite a hard plastic and it wears
very well. I think you'll find the black delrin or the black nylon
both have carbon black in them - it's the usual way they manage to get
a black colour.

If you want to have a look at some pieces, there are pictures at;

http://stores.ebay.ca/The-Great-Indu...eNameZl2QQtZkm


If heat is a problem, delrin softens at a pretty low temperature
( say, around 300 F) - nylon's a bit more tolerant. Delrin is far
more slippery, and is known for its insulating qualities in white as
well as it's ability to be machined to extremely close tolerances.

Eric


Nylon is also rather porous, no? Or is that the "filled form"?

Gunner

Whenever a Liberal utters the term "Common Sense approach"....grab your
wallet, your ass, and your guns because the sombitch is about to do
something damned nasty to all three of them.