[radicooldude]

Picture my x & y axis leadscrew comming through the bearing block, then it shoots out about 1" (at a diameter of .313 or 8mm), then it reduces to a 10-32 thread for about .5". I am trying to directly couple my stepper to the leadscrew. My steppers are .25dia shaft. The problem I am having is keeping the leadscrew/bearing block from having zero backlash. This is usually accomplished by the nut at the end of the leadscrew, making it tighter to the block. If I direct drive it, the nut/threads will be in the way of the other side of the flexible coupler. So, I am looking to use a shaft collar/clamp and put that on the leadscrew riding up next to the bearing block, then tighten up the clamp against the block with the nut. Next, i tighten the setscrew on the collar, and remove the nut. Then I can attach the flexible coupler.

Problem 1) Where can I find any of these shaft collars?
Problem 2) I don't have much..maybe $5-10 for each one. Where can I find it this cheap? I am getting my flexible couplers (oldham style) from MSC for $10, and would like to get the collars from MSC. Anyone have any clues where to find them cheap?

Attached is a diagram to help show the info.
Thanks - Zachery

Please note: I HAVE NO LATHE. Also, I am 17, and not enough funds to buy a belt drive for each axis. I already have the bearing blocks and motor mounts..I just need to figure out how to mount it. Thanks -Zack

[Celtichawk]

I used Oldham couplers.
The shaft mounted one has been tapped 6mm, that way I can tighten it to remove backlash then lock it with the grub screws. Have a digital dro told me today I still have 0.001" after compensating on Turbocnc, real backlash is 0.011 on the X axis, I think my bearings are not square.

[KDN Tool]

Try MSC part# 35460476. It is an 8mm one piece clamp collar for @ $3 each. Part# 87856746 is a 5/16" one piece collar for @$1 each. Keep in mind that the micro mill bearing DIA is 8mm so the 5/16" may not fit easily.

Ken
KDN Tool