I'm planning on using the cheapy keystone 1/2-10 acme screws from enco in my next build.

I've got a few questions:

1. Can I use a standard 1/2" inner bore spider coupler to connect it to the motor?

2. How do you lock the ends of the screws into bearings?

3. Do the ends need to be machined?

Basically I'm a total noob with this stuff. If someone could point me to a thread, or explain to me what parts I'll need to go along with the screws, I'd be very appreciative.

I used the "precision" acme screws from MCSDirect. I was told that they have a better form for use as a leadscrew. The cost was almost the same as the screws from Enco (sister company). I machined the ends on my screws for bearings, a locknut and a shaft for motor connection. I am not sure about trying to mount a connector on an unmachined end, though I think some people have done it.

Alan

Check post #294 here: http://www.cnczone.com/forums/showthread.php?p=103317#post103317

Thanks Gerry, that looks like a good way to do it.

I don't have a lathe, and I'm not sure how much it would cost to get the ends machined.

I found 1/2-10 acme nuts on enco. I was wondering if they can be locked together like jam nuts on allthread.

Edit: It looks like Steve is using acme nuts against each other...

Did you get your machine put together? I wanted to use a 1/2 inch acme rod too without machining the ends....I'm not a metal fab type of person. I'm also interested in what type of end bearings you used with the un-machined ends. If anyone can add to the un-machined ends question......I'd appreciate any help I can get.

cutloose

Andy,

I was not able to find 2 start nuts for my screw (1/2” 8tpi 2start). I used locking shaft collars.
MSC 87856779. I did use locking nuts for my original 3/8 12 screw.

If you are able to get double nuts for your 10tpi screw, they would probably be easier to use, but I am happy with my solution. It does also require a spacer to keep the bearings from rubbing on the collar.

Steve

spider couplers work well , if you use pillow bearings they will lock onto the shaft , thats what i used on my system , cheap , easy , no machining involved

Let me make sure I understand how you did this....

Un-machined screw end.... through a bearing.......and then the locking shaft collar on the end to hold everything in place? What did you use on the motor end? How does it work?

Thanks....Tim

Cutloose, not sure if you are asking me, or others, but I’ll chime in.

This is how I did it without machining the ends.

For a 1 start screw:
Motor coupler, double nut, bearing, thrust plate, bearing, double nut.

For a 2 start screw:
Motor coupler, shaft collar, spacer, bearing, thrust plate, bearing, spacer, shaft collar.

As Jerry pointed out, there are two pictures here (http://www.cnczone.com/forums/showpost.php?p=102831&postcount=294) .

dertsap, please explain more how you used pillow bearings.

Steve

i used a spider coupler on the motor end and mounted the motors , spider couplers have the advantage of giving some forgivance if everything isn t dead nuts