I made mine like the one shown here:
http://www.cnczone.com/forums/showth...=anti+backlash the 8th post. I made my own acme tap. You can search the forums here, it's been discussed before on how to make one. The only thing that I did differently was that I chucked my piece of acme rod in my drill press and used a file to put the taper on it. It wasn't to bad, it took about an hour to do. So far the nut seems to be working fine, but I don't have much time on it yet.
jgro