I'd suggest a dial indicator with a magnetic base and stand. Mag base positioned on lathe bed top or front, indicator tip running on the end of the workpiece near centre front. adjust the steady's jaws until runout is near zero. That's it. The setup in your pic looks like there is lots of room for this method.

Hi Philip.

I've never used one either but I watched a doubleboost video on youtube yesterday where John set one up.

He mounted the work in the chuck, set the steady around the work piece, close / adjacent to the chuck. Adjusted the steady so the fingers just made contact with the work piece. Then moved the steady to it's desired location. The logic being that the workpiece and chuck would be very close to concentic close to the work piece and errors increasing as you move away from the chuck.

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I seem to remember that Sparey covered this issue in his book

You don't need to align the steady, just make sure it sits right

It's the workpiece that needs aligning, use a dti

can take a while, a dead centre in the tailstock helps a lot, then remove it for final tweaks

edit you can use other systems like the cutting tool touching but if you want good accuracy you must get a dti system setup

GL

Edited By Ady1 on 04/02/2021 11:32:22

I turned a nylon piece to be a close fit on the part diameter where the steady fingers were making contact, see in the video here. **LINK**

Emgee

DC31k mentions the use of small rollers instead of fingers. While this sounds like a good idea, I'd be concerned about small shavings being crushed into the workpiece. Fingers will simply brush the shavings aside. I have the same concern with roller blade guides on a wood bandsaw squashing resin onto the blade.

My favourite method is to turn a short length of material to the same diameter as the work to be supported by the steady. Then set the steady to that. I also prefer to hold the work in a four jaw chuck so it can be held true. Inaccuracies can cause some interesting geometrical errors.

In extreme, a poorly setup steady can cause the work to "walk" out of the chuck jaws.

John

I would align the workpiece first and then carefully bring the fingers into contact, using a dti to make sure that a minimum of deflection was present. If the work needed turning at the point where the fingers were going, I would attempt to turn a portion near the chuck and then turn the workpiece around if possible. I made a set of fingers with little ball races for less friction and no wear. As already mentioned, a collar could be used to run on if the marking was not desirable. A piece of card should be cut to form a barrier against swarf getting stuck in the fingers.

Even with medium hard steel and rollers, marking is likely, the steady marks show on this spindle, but do not matter, fortunately.