Hi all,
I’ve been using our Shapeoko and VFD spindle for around 1000-1500 hours or so.
Recently the VFD spindle started making a whirring / chirping sound. Videos at the bottom of this post.
Symptoms: It happens most prominently at lower RPMs, at 8000 it’s very consistently present. It so far seems to go away as I continue cutting, but will intermittently start again at lower RPMs. As RPMs increase, the sound mostly goes away entirely, with occasional ‘chirps’ here and there.
This sound occurs with different bits and collets, no difference in the sound quality.
I recorded some high speed (as high as my phone will allow) video and watched it in slow-mo, and I can’t see any wobble. I can’t find anything loose on the exterior of the spindle, it’s clearly coming from an internal mechanism. My cuts are still clean and accurate. However, this sound is concerning me and I’m worried it’s the precursor to a real problem.
Any input would be greatly appreciated. I’ve got a steady stream of cuts that need to happen and can’t afford to have this spindle go out on me. I’m not confident on opening this up and diagnosing the problem myself, although if someone here has can point me to something specific to look for I can certainly get through some basic maintenance.
Here’s a video of the spindle running at 8000rpm with the sound very prominent:
Here’s a video of the spindle running at 24000rpm without the sound. The video features a spindown to stop, the sound does not appear at any time:
It seemed to go away after warming up the spindle for a bit through the rpm range. I’ve done a lot of cuts since then and the sound doesn’t seem to be much of an issue.
I have noticed however that it makes this sound when the ambient temperature is colder <60-50 degrees, maybe that has something to do with it.
It hasn’t affected the quality of my cuts or failed, but I have noticed a slight decrease in torque when milling steel.
I have been running a spindle warmup routine e very day before starting cuts. The spindle makes the noise during warmup and continues to do so when cutting, although intermittently.
It never goes fully away.
I want to make absolutely sure this isn’t a precursor to a real problem.
It’s good to know I’m not the only one though
Is the sound coming back intermittently related to when the tool makes contact with the material?
If not, it’s probably not indicative of a major bearing issue, especially if the quality of your cuts isn’t changing. I wouldn’t worry too much about it as there isn’t much you can do in this case, although I get that it’s probably annoying to have to worry about it eventually failing. For what it’s worth, I’ve ran and pushed my spindle a good amount since then and haven’t had anything major happen.
Taking the spindle apart and replacing the bearings is a pretty involved process as you’d want to use a press to get the bearings out. With the fact that it’s not really affecting anything other than making a sound, I would just run it for now and go from there.
Hi
Take your spindle out of the mount and lay it on it’s side. Brace it so it does not move and start it. run it up to 16-18k or so and let it run until it gets nice and warm. The chirping should go away as the lubrication is re-distributed.
Yep, sounds like grumpy bearings, my (cheap Chinese, non Carbide) spindle made those noises too, I opened it up and re-greased the bearings properly and they stopped cheeping at me. Given this is the Carbide spindle, if MC’s trick doesn’t work I’d talk to support.
This solves the issue. Other solutions may have worked for others, but in my case I run a warmup routine every day before running jobs, and the sound happens regardless.
Turning it on its side and running warmup routine has the sound still occuring initially during warmup, then for a minute or so after, but died down shortly thereafter.
Thank you for this. Will do this occasionally as part of the periodic maintenance.
No, the sound appears to be unrelated to tool contact with material. It happened often during spindle warmup, and also in the spin up before a cut after tool change before bit begins touching material. It did not necessarily go away when cuts began.
Issue was solved by another comment involving running warmup routine with the spindle set horizontally to let gravity pull redistribute lubricant