I didn't know what else to call it
Hefty Tool Post Block
© Frank Ford, 2008; Photos by FF

My lathe is a Hardinge clone imported from Taiwan by Sharp.  It's nominally 11" swing and only 18" between centers.  So, sometimes, bordering on often, the compound gets in the way of the tailstock.  I cecided to make this little adapter so I could simply take off the compound entirely for regular turning, facing, boring and parting.  It makes drilling a bit less cumbersome, too.  And, as a bonus it eliminates one source of movement and vibration during heavy cutoff operations.
Here's a view of the compound with the QC tool post mounted.
I removed the compound altogether and made some measurements to make an adapter.
As it happened the only piece of steel I had at the ready was just big enough to cover the swivel area.  It was a slice of cold rolled round. I had thought it would be good to make it oversize, but settled on the convenience of using what I had on hand.  Sticking it in the six jaw chuck, I faced one side and trued up the diameter a bit.
Flipping it around in the chuck, I used the "Set-Tru" screws to center the piece on my turned area so I could continue turning the diameter.
After I finished up the outside, I faced the surface and turned a "spigot" that would fit the central swivel area on the cross slide.
Next, for some mounting bolts. The original compound is secured by two bolts, and I figured to beef it up a bit, so I made four duplicates from cold rolled 1018 steel, first turning the bolt diameter.
Then threading the ends.
And finally, finishing off the heads to match the configuration of the original lock-down bolts.
Now, if I'd had a big chunk of cast iron, I would have made the entire deal out of one piece, but since this was a "scrap box" job, I had to bolt together two parts. As usual, I was "designing" as I went, so I milled an arbitrary ledge across a section of the adapter plate.
This is a hunk of steel, also from the scrap box.  I milled a matching ledge on it to fit up with the adapter plate.
I drilled my four mounting holes around the perimeter of the plate, and four more holes to bolt on the upper piece.
One thing I really wanted to get right was the finished height so my tool post and holders would not need to be changed when I switch from the compound to this new tool post setup. I set up a dial indicator mounted on the lathe bed so I could simply move the carriage over to clear it and put on my new part, leaving the indicator ready for a direct reading.  I came back to check the height as I worked along.
The bolts in place.
I bolted the pieces together to set them up for a reading, and took them apart to work down the upper block to get the height correct.
I milled it to within a couple of thousandths.
And, finally used the little surface grinder I'd found locally (on eBay, no less) to correct the height and produce a nice finish.
It took a few tries, but I got the height dialed right in.
Then I set about duplicating the T-slot from my original compound.  First a roughing cut. Not long ago I disovered the joy of using roughing end mills.  They really do a job!
Then some cleanup passes.
And, finally the T-slot, using a Woodruff keyseat cutter.
Once I had the upper block all dimensioned and ready to go, I added the simple finishing touch by beveling the corner edges.
I used some of these hex key socket nuts to secure the hold-down bolts that run up through the upper block.
I cut the rear bolt a bit shorter, of course.
Now, this is really one of those "do you really need it?" projects, but it's also part of my learning process, so I really enjoyed the project. Here, I'm parting off a two-inch rod as a first test - and it's working well.  I enjoy not having the compound in the way, so I'll probably keep this thing on until I next need to do a single point thread or taper.

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