Strong vibrations in ball screw linear actuator - is it normal

[mbridge87]

Hey everyone,

Thanks so much for the help so far. I’ve contacted the company I purchased this from to see what their opinion is. In the meantime, here are answers to all your questions:

1) The noise still persists when taken off the table. The table is extremely strong and sturdy and the slider was held down with G clamps but it was worth a try.
2) The noise does seem to coincide with the rotational position – see video below – I also notice that the noise seems to be worse when travelling away from the motor in the centre of the slider. In addition, there seems to be a noise like sand/metal inside almost like it’s grinding. You may be able to hear this on the video.

https://drive.google.com/file/d/16y3...ew?usp=sharing

3) Problem does remain with camera mount removed. Problem also remains when on the floor
4) Taking everything apart will be my next step
5) The table is something I use for photography / videography. It’s rock solid, weighted down, and the slider is held in place with G clamps. It’s only temporary but I’d be surprised if it was causing any issue. I have put it on the ground and the issue persists.
6) Pressing down on the slider as it moves has very little effect. It does decrease the vibrations a little but the main nasty noise is still there.

I think that answers all the questions. Here’s another video which shows the slider moving back and forth a couple times. The noise seems to be worst in the centre of the slider when it’s moving back from the motor side.

https://drive.google.com/file/d/170V...ew?usp=sharing

Apologies I seem to have filmed that video upside down...new phone.

I think the next step is clearly to take it apart and see what’s going on. I’ll wait to hear what the manufacturer says first though.

Side note – Where is the best place to purchase something like this from? If my budget were say £700 for something similar, where would you guys go? I know £700 is not a huge amount for a ball screw slider like this.

Thanks again

[Doddy]

I also notice that the noise seems to be worse when travelling away from the motor

I think the next step is clearly to take it apart and see what’s going on. I’ll wait to hear what the manufacturer says first though.
Thanks again

Agreed with dismantling... a bit at a time. And appreciate you wanting to sanction this with the supplier first.

Interesting observation on moving the platform away from the motor (screw between bed and bearing block (or motor) in compression). My random logic would be to check on the tightness of the nut on the bearing block behind the motor coupler... or for mechanical interference in this area (or between coupler and motor - explains the rotary position association), or even if the bearing blocks are bolted tightly down. Pure speculation of course.

Of interest (and what would make me cautious with running ahead with disassembly) is how motion is achieved with the dust-proof guard in place - does that move (conveyor-like) with the table? If not (and I've read a couple of sites that intimate that a stainless steel band is fed into the carriage - around a couple of rollers... and these would require lubrication... but that would all be explained in the product literature). Again, pure speculation.

Okay, out of ideas... but watching this thread with interest.

[JAZZCNC]

Sounds like you have a few things going off here.

I'd definatley say this is something to do with the linear rails or ballscrew alignment, or bent, etc, as it doesn't take much to cause binding. Possible end bearing supports are lose or poorly fit bearings.

I'd also say because of the grinding noise, which is common with cheap Chinese ballscrews, the ballnut needs stripping and cleaning.
It's common for Chinese ballscrews to not be cleaned properly at the factory so grinding dust etc is left in the ballnut. That said I wouldn't recommend you go stripping the ballnut down without knowing a little about how they work and being prepared and setup to do it, other wise you'll have dozens of little balls all over the floor.!!

Side note – Where is the best place to purchase something like this from? If my budget were say £700 for something similar, where would you guys go? I know £700 is not a huge amount for a ball screw slider like this.

What length do you need.? I could make you something like this easy enough. PM me if you want to discuss it and I'll give you my details.