Spindle clerance

[Drei]

Hi,

I have discoverd that i have a 0.01 to 0.02 runout in my milling spindle. Is it normal to have that clerance or do you have any. Any ideas what can i do ...
i measured the clerance by placing the dial directly in the spinndle inside..

Thanks
Drei

 

[Jasonb]

If thats mm then its not too bad for a hobby machine.

Jason

 

[Mainer]

I'm not sure what you mean by "clearance" in this context. It sounds as though you are measuring runout. If you're measuring in millimeters, as Jason says it's not too bad -- half a thousandth or a bit more. It could be better, but it shouldn't kill you.

If you're talking 0.01" to 0.02" on the other hand...you got a problem. Are the bearings loose? There should be absolutely no shake in the bearings.

 

[rake60]

If the spindle bore you are checking is tapered and your indicator needle is set on a taper,
the T.I.R. reading will be magnified.

Rick

 

[Drei]

What do you mean by magnified?

Thanks guyes
Drei

 

[Jasonb]

If you set the Dti so it reads at right angles to the spindle taper it will read true, if its reading say horizontally you will actually be reading the hypotinuse length but on something like a MT taper its not really worth worrying about as the difference would be unmeasurable with out tooling. Unless Rick knows something I don't?

Jason

 

[rake60]

The indicator needle on a taper needs to be tangent to the angle for an accurate reading.
If it is at an angle on an angle your reading will be exaggerated.
In the realm of .001 to .002" it would be noticeable.

You may get a better reading off of a piece of drill rod or an end mill mounted in a collet
or end mill holder.

My own X2 mini mill has an actual spindle runout of .001"
It has never proven to be a significant problem for me.

Rick