ER32 Adapter(purchased)

[stevec]

There is something different about the way the chuck registers and the way the collet chuck does.

I would never recommend comparing inside measurements of a bore to outside measurements of a shaft/spindle with a vernier if any kind of precision is required.

I was thinking of you locating another Myford owner and taking your chucks over to do a test or two on his Myford but I really don't think there's anything wrong with your Spindle or 3-jaw. It just boils down to the collet chuck adapter.