Thread: Looking for CNC parts

Hi Jimmy,
Good to see you surface again. Is it cold in your part of the world at the moment?
A 900 by 600 is a good mid sized machine. They get very expensive to make once you start going over that size.
Quite a few of us have been getting our linear gear and screws out of China. They are priced well comparted to local stuff and equivalent to buying second hand ex USA.
Link to the main seller is here.
There is a local guy selling motors and drivers competively and I am getting good feedback from people that have used him. So you are aware he is a ubeaut forum member but don't hold that against him.
Motors and Drivers

Hi Jimmy,

I have just recently purchased my rails and ballscrews from the seller in China that Rod mentioned. I highly recommend him for price and service.

Thanks Rodm And JohnH.Just one Question Rod.What is the difference between a ball screw and a lead screw? and which is best?
Theres a storm brewing at the moment Rod but otherwise the weather is not too bad
Once again Thanks Guys. Much appreciated. Jimmy

Hi Jimmy,
A ballscrew is a type of leadscrew. Other forms of leadscrews are acme thread, square thread of the type you would typically find in a bench vice. Leadscrews are used where you want to convert rotary motion to linear motion. Another form of linear motion popular to CNC is rack and pinion.

A ballscrew works the same as a threaded rod but there are ball bearings in the spiral of the nut. The ball bearings are retained in the nut and recirculate through a return tube. Advantage of this is that there is minimum friction even with very close tolerance contact area. Ballscrews are therefore much better than leadscrews as there is only minute backlash and low friction. Backlash is the slop between turning in one direction then reversing direction.

I'm not sure if I have helped here or just waffled on.

Thanks again Rod. I got onto the china site you recommended, and i've ordered my linear bearings.That's a good site.I'll keep in touch with my progress.
Regards Jimmy