Enlighten me on a Harding 4-Jaw chuck please

[petcnc]

Since each jaw adjusts individually you only need to grind each jaw face to be 90 degrees with some type of fixture or by eyeballing it

I do not trust my eyes anymore for that! I'd better use some fixture.
Thanks Mark
Petros

 

[markba633csi]

An accurate machinist's square would be helpful

 

[Silverbullet]

If the jaws are bell mouthed I'd be sure to grind them on the chuck . With them under holding pressure. , I suspect it's not the jaws but the chuck slots or jaw slots. .

 

[petcnc]

The guy gave me an extra £15 ($20) off for the missing key!
I think £186 is a fair price for a PB chuck, although postage is quite a lot (£37)