I've been slowly working on converting my old CNC mill back to manual.
Bought a set of new lead screws on ebay to replace the ball screws, but
they weren't an exact match for this old Millport. To get the Y screw to
line up, I had to machine shims for the knuckle to bring it up to the
right height. Y axis is SWEET, about .003 backlash. That was the easy one.

On the X axis, needless to say, I have a similar situation, however the
end bearing supports can't just be shimmed. After much consideration,
I've decided to drill out and tap the 3/8-16 holes to 3/4-16 and fill
with short lengths of all-thread. These will be Loctited and pinned.
Went this large, as it allows me to drill out existing holes on center,
but the new holes will remain entirely within the plugs.
I'll then align the bearing supports, transfer punch, and drill/tap new
holes. With this repair, it'll be good as new, and anyone down the road
can fit a power feed to the X axis with no hassles.

Thing holding me up was drilling these out. I have a customer that was
willing to loan me a mag base drill, but this project is one that goes
in starts and stops, and I didn't want to have his drill tied up.
A Cole drill seemed the obvious answer. Last year when money was tight,
they seemed to be all over eBay, sometimes 2-3 listed at the same time.
Now that I've got the coin to spare, not one to be found on my search.
Well, dawned on me last week that I was only looking in Business and
Industrial. Opened that search up to all ebay, and there was one listed,
under collectibles! It's now sitting on the bench here being cleaned up.
Not as pristine as I would have liked, but more than serviceable and now
I can move on with getting the Millport ready to sell.


Jon