How to fix the lead screw end?

[bonmotwang]

Searched the forum, didn't find my answer. May be wrong keywords :-D

I have one DIY style CNC router at home, pretty good. It does 3D wood carving perfectly.

Now I am designing my own in solidworks. One question came up is how to mount the lead screw end. My plan is to use the coupler for one end and bearing for the other end. So one end is actually held by the stepper motor. My question is for the other end. What is the "typical" to mount the other end to stop the lead screw move back and forth?

Thanks

Paul

[microcarve]

Here's how I do it.....

Green is your bearings.

Blue is a washer that prevents the collar from rubbing
on the outer bearing race.

Bearing blocks can be what you showed, or aluminum/plastic/wood blocks
with the bearing fixed into them.

The clamp collars prevent any end to end movement of the screw and also
allow for extra extended length for the coupling.

They also don't cause need for a flat on the screw or use set screws that will
damage threads....and destroy any plastic nut that's installed or removed.


John

[bonmotwang]

Thanks John
I guess I don't have to use the special ball screw support bearing then. they cost about $25 to $30 (as shown in the attachment).

[microcarve]

Sorry, I somehow assumed acme screws....

If you're putting the $$$ into ballscrews, then I'd use the right
parts for those.


John

[bonmotwang]

One 1604 with the nut is about $26, about the same price as the ball screw support. Do you think it is the right combination? I am designing a CNC for myself now.
Here is a peak of my 3D model (Almost 1 to 1 from a design posted on the net).
Thanks
Paul

[microcarve]

Wow!...That's a Super-cool design....

Personally, I'd pay the price and get the right stuff.

The design alone looks like it just deserves the *right* parts....



John

[bonmotwang]

Thanks John
I agree. Better just use the right thing.
Paul

[eaglezsoar]

Here is another way to do it.
The following link shows how to use thrust bearings with a lead screw using parts from CNCRP. Hobby Robotics » My CNC Engraver (Part 1)

[LazyMan]

DumpsterCNC sells thread clamps that allow the preload to be adjusted easily for this exact purpouse. If you have access to a lathe to turn down the ends of the acme rod then you can use the bearing blocks. There really is nothing special about bearing blocks. Just two angular contact (sometimes radial for lower loads) bearings with shim in the middle.

[bonmotwang]

Thanks guys. after more research this is the way I went.

In the motor holder there is a standard bearing for support only.