Centroid Community CNC Support Forum

That doesn't look like a ball screw to me?
And yes, that coupler doesn't look right either can you take a better picture perhaps with the motor coupled to the screw?

I didn’t have the motor out with me in the shop but here it is:
The shaft slips into the spring Collette- like coupler. The coupler is threaded onto the end of the threaded rod.
More photos of the lead screw (definitely not a ball screw)

Clearly looks to me like the motor shaft was spinning in the coupling.
Looks like an Acme screw.

I'd probably update that assembly with a ball screw and proper coupling if you can't tighten it up properly

I tried tightening it up and I could not tighten it up enough. It slipped less often, but any slippage at all really messes everything up.

Do these things come in standard sizes such that I can find a form fit and function replacement or am I going to need to do some machining to replace it?

ericbowman wrote: ↑Thu Feb 10, 2022 10:16 am I tried tightening it up and I could not tighten it up enough. It slipped less often, but any slippage at all really messes everything up.

Do these things come in standard sizes such that I can find a form fit and function replacement or am I going to need to do some machining to replace it?

Well, you will likely have to do a bit of machining. Do you have any machining capabilities or know of someone that could help?

How are the X and Y axis driven? Rack and pinion? Acme Screws like Z?
What will you be machining on your router?
You could determine the pitch and diameter of your current ACME screw and replace it and the nut. But you would still likely have to have the replacement screw machined. If I was going to go through this work, I would replace it with a ballscrew.
Pull the screw out. Determine its length, diameter and pitch (how many threads in an inch)
What is the size of the thrust bearing i.d.

Take it apart and take more pictures of it disassembled.

Marty

Back working on this and the noise from that Chinese VFD is so bad it’s unusable. Is there a VFD you recommend with a 4KW spindle? The spindle is a Chinese one too, is that Likely to produce emi as well or just the VFD?

You may not have it grounded properly or you're not using shielded cable and grounding that properly either. I've used many Chinese VFD's and spindles and get no noise in my systems. Post pics of the wiring and spindle power cable you are using.

Here are photos of how I've set everything up. They're all grounded to a ground plane and the shielding is grounded from one end of each signal that goes from the control to the driver. I do not have the VFD wires shielded and I do not have the wires that go from the gecko drivers to the motors shielded. The first photo is of the whole thing, and then I've included closeups of everything.

the components are attached to the plate with risers to avoid inadertant electrical contact. The VFD has a filter on the end that is plugged into the wall and ferrite chokes on the side going to the machine. I had it on the plate, and I had the filter on the plate, but the noise seemed even worse then, so I have temporarily insulated them from the ground plane.