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Logan Lathe CNC Conversion

To mount the ballnut the way I wanted, the first thing I needed were some fairly precise measurments.
To get a good number for the space between the apron and the nut, I used a Starrett adjustable
parallel, slipped in until it just held itself in place, and then tightened.

Logan Lathe CNC Conversion

With that number and other measurements taken directly from the nut itself, I whipped up this
highly detailed and aerospace-quality blueprint, which I then transferred over to a piece of cardboard.

Logan Lathe CNC Conversion

The cardboard in turn was used to mark the cut lines in the round stock. It was easiest to use round
to get the block size I wanted, as plate or bar of this thickness isn't easily available locally.

Logan Lathe CNC Conversion

Again, a 90-second trip through the bandsaw saved me literally over an hour of mill time, and saved the excess
as material I could use for other projects. At 3", this is the thickest chunk of aluminum I've cut with this saw,
and it sailed right through, cutting all four sides in less than two minutes.

Logan Lathe CNC Conversion

After that, it's a typical Machinist 101 exercise to square up the block.

Logan Lathe CNC Conversion

After that I located, drilled and bored a socket to fit the ballnut.

Logan Lathe CNC Conversion

And, using the specs that came with the ballscrew- and a little math to convert that weird
European stuff into normal units- I drilled and tapped a bolt pattern to attach the nut.

Logan Lathe CNC Conversion

A quick check shows it fits nicely, and there's just a smidge of "slop" in
both the socket and bolt holes, so that the nut can self-align during installation.

Logan Lathe CNC Conversion

I'd left the block oversize so that it could be  fairly precisely fitted into place. It was a bit
tricky to get a reliable measurment, but that adjustable parallel came in handy again.

Logan Lathe CNC Conversion

And, after milling it down to that precise measurment, a quick re-test showed it now fit perfectly.

Logan Lathe CNC Conversion

I'd been hoping I would be able to clamp the two pieces together with a C-clamp or the like, remove them
as a unit and drill them together, but there wasn't room with it in place on the lathe. I was instead forced to
simply mark the apron with a marker, and with only a little guesswork, drill a mounting bolt pattern.

Logan Lathe CNC Conversion

After that, I reassembled everything yet again, and simply used a transfer punch to mark the ballnut block.
I was then able, with considerable care, to copy the bolt pattern on the block, and drill and tap it for the bolts.

Logan Lathe CNC Conversion

After verifying everything lined up, I flipped the apron over and countersunk the bolts.
The slight "float" of the nut to the block should hopefully take care of any minor misalignment.

Logan Lathe CNC Conversion

And there we have it.The apron is solildy bolted to the saddle, and the ballnut is solidly mounted to the apron.
Why didn't I just bolt the block to the underside of the saddle? Well, let's go find out...

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Information contained in these pages is for reference and entertainment purposes only.  Our methods are not always the best,
quickest, safest, or even the correct ones. It's up to you to know how to use your own machines and tools.
Keep your fingers away from the spinny blades o' death and you should be all right.