Motor Face Runout
Motor Face Runout
(OP)
Does anyone know of a way to face the base of the motor to improve runouts, both face and register? Does anyone make a machine for doing this? I'd like to get down to 0.001".
Thanks, Mike
Thanks, Mike





RE: Motor Face Runout
Do you want to get a flatter base?
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RE: Motor Face Runout
thanks, MB
RE: Motor Face Runout
I have seen various milling setups for use out in the field that would fixture to an existing shaft or hole.
One style was a fairly small spindle on a radial arm that would attach to an existing shaft. Once the spindle arm was attached they could do some precise onsite machine work such as facing, bolt circles and grooves. It was slow since they were not ridged enough to take a large cut but it got they job done. As far as I know these were home made setups.
Barry1961
RE: Motor Face Runout
http://www.cpmt.com/tool_over_ff.php
"Venditori de oleum-vipera non vigere excordis populi"
RE: Motor Face Runout
RE: Motor Face Runout
Many low thrust vertical motors have single row deep groove bearings, these have axial clearance upwards from 0.010 to 0.025 pending on size. Your expectation here is impossible
Motors with 2 angular contact bearings at the top and a lower single row deep groove will give you the best results .
We have had lots of luck by checking the TIR axis to the face from the shaft, (must be hanging vertical) and mark the runout as you rotate the shaft, spin several times to ensure repeatability. Matchmark, Remove the bracket set up on the lathe or VTL and duplicate the runout. machine off the high spots. Reassemble and recheck. Usally we get with in 0.0015. The bigger the motor the tougher the problem
Small motors can be machined assembled in a lathe.
1 Preload the bearings to take out the looseness
2 Set in lathe in dead centers with the live center in the headstock, keep the shaft still and drive the motor around the shaft, machine the flange face flat.
3 Dont forget to remove the preload from the bearings.
4 Check TIR
RE: Motor Face Runout
I'm assuming that all of your customers are stupid and you know more about motors than they do, Right? I don't think that my tolerances are too tight, I'm just trying to meet a customer's specification with some kind of acceptable capability in our process. This is not a NASA project but one that requires very close tolerances. And with most standard manufacturing practices, I agree that this may be impossible. I've got a shop full of standard manufacturing practices and don't have the equipment that I'm asking for here. Most of us are still in business today because we've given the customer what he asks for. And we all know that customers can be a little ridiculous in what they ask for sometimes. But when your customer asks you to meet a specification and show that you have process capability with Cpk's to prove it, what should your target values be? I know all of us have seen customers requesting tighter tolerances in areas of vibration and efficiencies, this is just another case where they feel it is required. If I want the business (and the 60% GP), I'll have to show the capability or somebody else will.
MB