cnc lead screw mounting

[hpghost]

I am making a cnc miling machine for hobby.
can some one post some photos and/or drawings of the way he has done the lead scew installation. on the motor side, I have used a coupler...but on the opposite side...I don t know how to do it in order to have the best mounting.

[chuckknigh]

The best advice I can give you is this... Separate the mounting of the lead screw, and the driving of the lead screw, as much as possible.

Here's what I mean...

Take your axis, and install your lead screw. Now, it should be completely self supporting, and tensioned between appropriate bearings. You can actually do it with a bearing on only one end, but this is a less than ideal solution, because it places loads on the bearings inside the motor...which are not designed for that sort of loading.

Now that you have a self-supporting, self contained system...connect your motor to the end of the screw. This can be with any sort of coupler you want...from the high dollar helical couplers to the lowly air-hose couplers, or even througha pulley or gear arrangement. The point is that it's a separate step. NO loading is put on the motor, and it lasts longer that way. PLUS you can tension your lead screw, to reduce whipping at higher speeds.

-- Chuck Knight

[solarchimesam]

Good day,
Any suggestions on a site I can purchase reasonable priced u-joint rod couplers?
I am using 1/4 20 threaded rod and ACME but this is for the 1/4 20 right now.
Thank you.