PM728VT spindle bearing question

[tominboise]

I just bought a new PM728VT mill and got it delivered last week. I have been getting it set up and did the spindle break in per the manual, running it at various speeds for a minute, etc. Anyway, when I turn the spindle by hand, the bearings feel notchy to me. I am wondering if this is normal or if something might need adjustment?

 

[ShagDog]

First of all, congratulations. I don't think it there is an "adjustment" for the bearings. Hard to quantify "notchy. " I just went and turned my 728vt spindle by hand, and it did not spin freely (which I think is normal); but, I could hear it turning. Runs fine by the way. Hope that helps.

 

[tominboise]

First of all, congratulations. I don't think it there is an "adjustment" for the bearings. Hard to quantify "notchy. " I just went and turned my 728vt spindle by hand, and it did not spin freely (which I think is normal); but, I could hear it turning. Runs fine by the way. Hope that helps.

Thanks for the info. I feel a distinct click, click, click in my hand when I turn the spindle.

 

[ShagDog]

I went out and checked again. Feels like its is meshing with gear (very difficult to describe but I guess could be considered a "click"??), but, I don't think there are any gears. So I loosened the drive belt completely, and the feel of "meshing with gear" was gone. Have you completely loosened the drive belt to see if the "click" feel is gone?

 

[stupoty]

I went out and checked again. Feels like its is meshing with gear (very difficult to describe but I guess could be considered a "click"??), but, I don't think there are any gears. So I loosened the drive belt completely, and the feel of "meshing with gear" was gone. Have you completely loosened the drive belt to see if the "click" feel is gone?

Good point , op might be feeling "cogging" from the motor as it's a DC brushless so you might be feeling the magnets.

Stu

 

[MikeWi]

As was said earlier, just loosen the belt and try again. I'm sure it's just cogging.

 

[verbotenwhisky]

Thanks for the info. I feel a distinct click, click, click in my hand when I turn the spindle.

If it worrisome I suggest that you remove the belt or at least take the tension off of it and turn the spindle without turning the motor. What you may be feeling is the motor stator rotating with magnetic resistance.

 

[tominboise]

Ok, thanks for the info, I will loosen the belt and try again.

In other news, I did make my very first chips with the machine, starting to square a small block of Al for practice and to see how the tram is on this machine. It worked pretty well (seems to me, I am new at all this). I used a used, 7/16" HSS two flute cutter at 1500rpm, 0.030" depth of cut, running the x axis with the feed unit. First of many chips to come, I hope.

 

[tominboise]

Ok, dumb me- I loosened the belt and the spindle turns as smooth as butter, so crisis solved. Thanks for all the tips.