Poor Man’s Lathe DRO (ARO?)

My lathe doesn’t have a Digital Read Out (DRO). This isn’t an issue on a high quality machine because the hand-wheel increments are accurate. Well, on a cheap lathe, they’re merely suggestions at best. At worst, a quick way to scrap parts.

Given that, I’ve been thinking for an age on how to go about making accurate measurements on the lathe itself.

Carriage travel is fairly straight forward: A 2″ dial indicator on a magnetic base, plonk it down on the ways perpendicular to the carriage.

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The hard part is the cross-feed. Bigger lathes have plenty of places to put magnetic bases, but real estate is pretty sparse on this one. There’s plenty of space on the cross-slide itself, but that is what I need to measure, so it’s a non starter.

Finally, I found the solution. A Mighty Mag base. It’s a strong magnet, with a very narrow footprint. With that, I can steal the arm & indicator holder from a Noga-style indicator base, make an adapter(on the lathe!) to connect the 2, and that would allow me to affix the indicator to the carriage, and indicate the amount of travel in / out.

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I wipped up the adapter:

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I used the drill press to drill a 3/16″ hole about half way into the shank to give the pinch bolt something to bite into and secure it… securely… into the mag mount:

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The parts, laid out for assembly.

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And finally, on the lathe. The left side of the carriage is about the only spot I could reasonably put it where it wouldn’t interfere with the hand-wheels or power-feed controls and be bumped around. Almost as though it’s made to go there:

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Boom. Analog Read Out (ARO? Is that a thing? It is now…) complete!