I bought the HobbyCNC plans for building your own machine, and it tells you to buy the leadscrews from Kerk Motion Products. That's what I did and I recieved the 3 leadscrews at my doorstep just a few days ago.
Here's the problem:
Drawing number 14 in Dave Rigotti's book shows that a short section of one end of the leadscrew is completely rounded to accept a coupling. I just looked at the leadscrews they sent me and there is no rounding down at the end. Am I missing something? Or did Kerk Motion screw up? It just doesn't seem right to attach a coupling set screw and have it dig down into some acme threads.
Any help would be appreciated.