Re: leadscrew, acme screw, threaded rod, ballscrew

> So leadscrew is not a special form the threaded rod that one can
> purchase from any hardware store? So the leadscrew in the respectable
> Sherline is a threaded rod?

"leadscrew" is a term used for a linear drive screw. I've seen all 3 types used, but acme and ball screw are all you'll see on well built machines. I've seem hardware stor threaded rod on some homemade machines. I don't know the sherline models, but I'd bet they use acme rod.

If you want to really confuse an Ace Hardware employee, just go in and ask for a lead screw. :) You can buy acme rod and bronze nuts from MSC or McMaster-Carr.

> I see that acme screw is a kind of square thread. But I see also ball
> screw using square threads. Are these acme screw? So is the
> difference between drives using acme screw and ballscrew existing
> only in the type of drive nuts they use - with the ballscrew having
> recirculating balls?

I think acme rod comes in different thread styles. I've only used square thread acme rod. It also seems to be the most popular. I've never used ball screws (out of my price range), but based on the price of the rod vs. acme rod, there has to be a difference. I don't reely know much about ball screws. Once I priced them, I started looking at other alternatives.

Ross