Actual metal content

Just received my April/May copy of "Machinist's Workshop". Wonderful
article by Jon A. Nelson on making a Too Post Grinder.
While this project may be beyond my capabilities, I was very impressed by
the detail contained therein. As an example, he has you holding the
outboard end of a 1" by 9" (drill rod stock) spindle in a steady rest
(making sure you dial it in so it runs true) in order to center drill the
end. Until now I've simply shoved my stock well into the headstock and slid
the tailstock all the way to the left to do center drilling etc. I've also
watched my center drill wobble quite a bit since my 3 jaw chuck is not the
best.
Question: I do own a steady rest. (1947 ± Le Blonde 13" lathe). One of
the fingers is missing. As long as I'm going to be making a finger, should
I make three (out of steel) and install ball bearings, or just use friction
(brass)? Advantages and disadvantages?
As I mentioned, great article, possible a little too elementary for the rest
of you.
Ivan Vegvary
Reply to
Ivan Vegvary
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I made a ball bearing one for water well pipe, works good for this irregular material. For everything else, I like the brass unit better. Just my 2 cents
Karl
Reply to
Karl Townsend
The bearing rollers do not require coolant of lubricant while the brass ones should have coolant or lubricant on them. I made a set out of Ultem 1000 that I had left over from another job and they worked better than the brass.;
John
Reply to
John
Blonde 13" lathe). =EF=BF=BDOne of
The ones with roller bearings can cause irregularities when a chip goes through the roller. Engineman
Reply to
engineman
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I think that actually bronze, not brass, would be the better contact point material.
Ball bearings can have benefits, but if chips get in that area, they will be rolled into the workpiece, thus marring the finish and causing it to run off center.
If you can clean the workpiece, and set up shields to keep chips out of that area, the ball bearings can be better for heavy cuts.
For something like cutting Acme threads on a long shaft, you want a traveling steady, not a fixed one, and there you would want bronze contact points broad enough to bridge a couple of adjacent thread crests.
The exception to the bronze points would be if you are cutting Acme threads in a bronze shaft, in which case you want some other material so you don't get galling.
Enjoy, DoN.
Reply to
DoN. Nichols
Greetings Ivan, I used to do a lot of really precise steady rest work. Ball bearing rollers are best for crappy work. Like steel with mill scale on it. When doing precision work the rollers have a couple major disadvantages. One is the hazard of getting a chip between a roller and the work. This will leave at least one dent, and possible three dents, in the work. The other major drawback of rollers is the tendency to roll the work to a smaller diameter so then the clearance increases and the work rattles in the steady. So for the best result use bronze pads and install an oiler on the steady rest. I use a drip oiler, the type with a sight glass to see the drips. I drilled and tapped the steady rest for 1/4 pipe to fit the oiler and drilled through 1/8". I use a bent piece of piano wire forced in the 1/8 hole to direct the oil right onto the part and right next to the bronze pad. The pads will wear a little to the work when you first spin the work. So adjust them and then as long as you have oil dripping on the work at the pads the work will be suspended by the oil and the work will run very true. Another advantage of the oil drip is the ability to spin the work very fast without too much heat build up. This prevents the work from seizing in the steady rest. Cheers, ERS
Reply to
etpm

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