How Do You Center a Steady Rest ?

Greetings Jack, I used to do a lot of steady rest work. The parts needed to be accurate so the setup was critical. One thing I did was add an oiler so there was a constant flow of oil to the pads on the steady. This kept them cool besides lubricating them. So, here is one way to get it really on center. Put the shaft in the lathe and indicate the outboard end so that it runs dead true. Then, use two indicators, one on the top of the shaft and the other at 90 degrees to the first. With the lathe OFF turn the adjustment screws until the pads contact the shaft. You will see the indicators move slightly. Adjust the steady rest pads until you have the desired pressure and the indicators still read zero. A less accurate way, but much faster and probably more use to you is to get the outboard end running true with a center in place. Then, with the shaft spinning, bring the pads into contact carefully with the shaft. You will feel them making contact if you take care. If the shaft runs out even a couple "tenths" and the pads are brought into contact slowly enough you will feel the momentary contact. If you have measured the runout beforehand you will then know just how much more to turn the screws. Good luck! Eric R Snow, E T Precision Machine

Would it also work to get it into the steady, mount the indicators to your cross-slide and run it up and down the bed while checking the indicators?

There is no better way to get a steady running properly than to do it while the machine is running, much as Erik suggested. The problem with a steady set up any other way is that you risk having the steady slightly off center, which often results in the part walking out of your chuck.

To get a steady running properly, all you have to do is get your part in the chuck, fairly well snugged, and have the steady in the desired position, jaws slightly backed off. You don't even have to have the top of the steady closed if you so desire. The part is highly unlikely to go anywhere while you're adjusting the bottom two jaws, which you do under power at slow speed. Do as Erik suggested, start tightening one of the jaws slowly, stopping while you still feel the intermittent contact of the rotating part. Go to the other jaw and do the same thing. At this point. very carefully bring in one of the jaws until you feel it making constant contact. You'll be able to feel it through the adjusting screw. Do this slowly so you don't overshoot center. Do the same for the second jaw, then close the top and do the same for the third. At this point you may wish to either tighten or back off all three jaws ever so slightly to insure the proper amount of running clearance, or lack thereof.

Setting up a steady by placing it next to the chuck and them moving it to proper location is to be avoided.

Harold

Mount your magnetic base to the chuck, put the point of the indicator against the shaft. Be a far away from the chuck as you can with out the indicator being affected by gravity as you rotate the chuck. Giving you a false reading. (Magnetic bases with fine adjustments are generally not good for this.) Rotate the chuck by hand and read the indicator. It works kinda like dialing in a 4 jaw chuck. Only you have 3 supports instead of 4. (Well sometimes you have 4 supports on a big lathes.) Read the indicator in line with the support and directly opposite the support. Adjust the supports while reading the indicator movement. Adjust the supports of the steady rest until the indicator reads zero all the way around. If anyone wants me to I can post pictures to the drop box, if it's not clear. Remember if you are not lined up properly the shaft will work out of the chuck, which could get really exciting at high Rpm's.

Richard W.

I made a whole bunch of idler rolls for my apple line water bin dump exactly this way. Step one was to weld in a four inch long solid rod inside the end of a 2" steel pipe. This rod was then turned to 1" for pillow block mounting. The idlers are 6 foot long, the chuck wouldn't even begin to hold it anywhere close. So, I set the bottom two jaws on a pipe stub next to the chuck, then slid it out five feet and adjusted the top one just slightly tight.

With a 36" long 1.125" diameter rifle barrel blank, I have the barrel mostly slid up into the headstock, dialed in on the bore in the 4 jaw, and cut the outside to be round. I take the barrel out, turn it around, dial in, and cut round the other end of the barrel. I slide the steady rest up next to the headstock and locate the three roller bearing of my steady rest on the round part of the barrel. I open the top of the steady rest, move it to the right end of the ways, loosen the 4 jaw, slide the barrel out of the chuck partially to reach the steady rest, dial in the chuck on the round part of the left end of the barrel, and then clamp the steady rest on the round part of the left end of the barrel.

When I made the bottom part of my steady rest, I was careful to build everything very stiff. I can go from loose to fully tightened with 1/8 turn of the steady rest lock down. If the steady rest can change height with how much it is tightened, that is no good.

Post ADCN

change from: I open the top of the steady rest, move it to the right end of the ways, loosen the 4 jaw, slide the barrel out of the chuck partially to reach the steady rest, dial in the chuck on the round part of the left end of the barrel, and then clamp the steady rest on the round part of the left end of the barrel.

change to: I open the top of the steady rest, move it to the right end of the ways, loosen the 4 jaw, slide the barrel out of the chuck partially to reach the steady rest, dial in the chuck on the round part of the left end of the barrel, and then clamp the steady rest on the round part of the right end of the barrel.

If your ways are worn from the tail stock sliding bank and forth, then you will be below center. Usually there is no wear under the chuck because the tail stock can't be moved under the chuck. because the cross slide/carriage is in the way. I have seen the tail stock as much as .090 low due to wear on the bed and underside of the tail stock. If you have a lathe that's in good shape you can do it as described above. If it's not, then you have to dial it in the way I described in my earlier post.

Richard W.