I could not find the thread about spindle run out.
Anyway, this spindle was OK but needed fixing.
I centred a boring bar in a vice, in line with the X axis.
Then did a short program to run from the edge of the boring bar to trim up the inside of the spindle. I went from X3.4 Z0.192 to X0 Z-24.0 These are mm dimensions on radius X axis and Z axis.This makes 8 deg /side taper.
I just offset the X axis until it cleaned up. The only important part of the setup is having the cutting edge on the centre line or just slightly above , in my case, to have Y at zero or very slightly on -Y by .05mm or so.
I used bearing blue to confirm the taper matching on a solid ER20 test piece I made.
Here is a link to the video showing the 4mm ball setting piece I made with a DTI on the ball while it is running. It is the same result when turning by hand carefully. You can see the boring bar mounted in the vice as well.
https://www.youtube.com/watch?v=ZK9jB_MFFLk
Hopefully this may help some one out.
Neil
Anyway, this spindle was OK but needed fixing.
I centred a boring bar in a vice, in line with the X axis.
Then did a short program to run from the edge of the boring bar to trim up the inside of the spindle. I went from X3.4 Z0.192 to X0 Z-24.0 These are mm dimensions on radius X axis and Z axis.This makes 8 deg /side taper.
I just offset the X axis until it cleaned up. The only important part of the setup is having the cutting edge on the centre line or just slightly above , in my case, to have Y at zero or very slightly on -Y by .05mm or so.
I used bearing blue to confirm the taper matching on a solid ER20 test piece I made.
Here is a link to the video showing the 4mm ball setting piece I made with a DTI on the ball while it is running. It is the same result when turning by hand carefully. You can see the boring bar mounted in the vice as well.
https://www.youtube.com/watch?v=ZK9jB_MFFLk
Hopefully this may help some one out.
Neil
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