I used a piece of Teflon rod I bought through ebay. Took it to the local machine shop, or local plastics shop so they could stick on their lathe to drill the hole. But come to find out, Teflon is pretty easy to drill. You just need a way to make sure it will stay true while drilling. Which is why I took the rod to the machine shop. Then the machine shop cut the rod into 1/2 inch pieces for me.
A regular stanley box cutter blade does the job real nice. You just have to grind the back of the blade to fit the inner hole is all. Now that I have used this cutter several times, I am sold on its use with goat rawhide for sure. I have not yet tried it out on horse rawhide, deer rawhide, or kangaroo rawhide, or rawhide for that matter.
Brian...