Pictures of DRO installations on classic South Bend toolroom lathes?

[rwdenney]

Yes, I got the bend wrong and it tilts up. But the reader is mounted straight and it only needs to be held in one spot. Ugly but I can live with it.

If it proves too weak, I can run a brace over to the taper attachment frame. But so far it seems sturdy enough.

Yes, I could only get the good taps to go in about a half inch, but finishing with the bottoming tap was enough for the screws that came with the scales. A bigger problem was the holes wandered off square in that gooey steel.

I drilled these in my old press—230 RPM. That’s pretty slow for a drill that size, but that’s what that stuff needed. The 350 RPM slow speed of my better press was too fast. Bigger holes tolerated it better than smaller holes.

When I broke the tap, I had to set it aside for a week while I thought dark thoughts. I even bought an aluminum bar 1/2 x 1-1/2 to remake it. But the new drills in the same McMaster order worked better.

Rick “at least the bandsaw would cut it” Denney

 

[rwdenney]

The Z axis is installed and the DRO is operational. (It’s labeled Y axis on the head unit, of course.) It was a LOT easier than the X axis, for probably obvious reasons.

I mounted the tail end as close to the end of the bed as I could without invading the curve of the casting on the end. I will still run out of scale by maybe an inch if I rack the carriage up against the tailstock at its most extreme position, but I keep a micrometer stop clamped in the ways at the end and it will stop the carriage before the reader hits the end of the scale. I could move the reader closer to the head end of the carriage and solve that problem, but where I mounted it is convenient.

Mounting was just drilling 4.2mm pilot holes in the bed casting at each end of the scale and tapping them for the 5mm x 0.8mm screws that came with the scales. I like cast iron.

Aligning the scale was not made any easier by the fact that the scales are extruded aluminum and not machined straight. But I found a position that got it without ten thou over its length both horizontally and vertically.

I used a couple of the aluminum brackets that came with the scales to mount the reader.

The bracket mounts to the back of the carriage adjacent to the bracket I made for the X axis reader. They are tight against each other and will help keep each other aligned. But the aluminum and steel combination is butt-ugly. Perfect for this lathe.

Calibrating the Z axis is a thousand times easier than the X axis, though I am now pretty happy with both. I clamped my better micrometer stop on the bed, zeroed out the Y axis…

…and then racked it out far enough to insert a 7” Brown and Sharpe micrometer standard. I’m happy with the result.

Shorter standards got similar results.

All that’s left is cleanup and switching the X axis to read diameter. And check it with an actual turning.

Next up is seeing if the surplus tailstock I bought is closer to being straight than the one on the lathe.

Rick “traveled every week for the last seven—glad to get this done” Denney

 

[rwdenney]

Both my scales aim down. Any real risk in not installing the dust covers? The X axis is doable but the Z axis reader bracket gets in the way.

Rick “both fairly protected, it seems to me” Denney