Centering Part In A Steady Rest.. ?

WesPete66

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OK, so how does one set up a part in the steady rest?
I have this part, a small shaft about 4.5" long, and it has a lug welded onto one end. I need to turn just a small bit off of the straight end. My plan was to center drill both ends, then turn the part between centers. I got the lug end center drilled ok. But now I'm setting up my steady rest for the first time, and how do I dial in the part to drill on center? Saw a video showing a dial indicator mounted on the chuck, but there's no room (maybe 3" between chuck and steady rest). help please?
 
Put the part or any round of the same diameter in the chuck, slide steady right up to the jaws and set it there then slide it to the end of the part.

Be aware that when a steady rest is misaligned it will sometimes walk the part out out of the chuck jaws, this is unpleasant at best.
If the part diameter is to small or rough for the steady make a catshead and indicate it like so, this is a 5" hot rolled bar that was not nearly round enough for the rollers
catshead_zpsbbnjm2iu.jpg
 
Not sure why you need a steady rest for a 4.5" long part. Not making sense as it would not leave room for turning. Between centers should work fine, but without seeing the part, its hard to recommend a setup.
 
It would appear from the description that this is a weldment, something on one end makes it unable to pass through the chuck in order to drill a center in the opposite end necessitating the steady.
 
Picture of part might help. How big is the welds lug? Can you open the lathe chuck wide and put the "lug" through to rest behind the chuck
and then chuck up the chuck around the shaft? Your description of both the part and the desired operation is hard for me to gat a hand on.

CHuck the grumpy one
 
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Sorry, have been having problems getting pics from the camera to this new puter.. Here is a pic of the part, 4.5" long. I need to turn down part of the length to fit the trip finger shown. The lug end is too big to fit inside my lathe/chuck. I can grip the lug end in the 4jaw, but it's not solid due to the cast shape. I need to support the end, and the center drill needs to be right on since I'll only be removing a small amount.. (oh yeah, the trip finger is hardened and I have no way to work it.)
Thanks for any suggestions!
ignitershaft1.jpg
 
That looks like a candidate for between-centres turning... It's something of a dying art, but was all we had before these new-fangled chuck things ;)

YMMV, but I'd probably:
(be certain the tailstock's aligned for this, unless you want to cut a taper or have it walk out of the chuck while you centre drill the shaft end)

chuck the shaft in the 4-jaw (or in a collet if I had one to fit) leaving some shaft accessible for a DTI, dial it in, centre drill the end with the existing lug;
put a centre in the spindle (may need to be an extended long-nose or cut-to-fit), flip the part then close up the 4-jaw lightly on the existing lug end just to locate it (I won't be running under power for the next few ops!) ;
dial-in the shaft (if it isn't dead on thanks to the new drilled centre), tapping the free (shaft) end to bring it true then put in a pop-mark lightly with the tailstock centre to hold it temporarily and recheck it's running true;
adjust the steady on the rod while up close to the chuck (and existing lug) and slide it out to support the shaft, tighten the 4-jaw;
Drill the centre in the free end (drill pressure will keep it firmly on the headstock centre if I don't pussyfoot about) then remove the steady for room to work.

Then I'd run it for the actual cut between headstock and tailstock centres, either with a drive dog (tricky with that lug) or bringing one of the chuck jaws in to meet the existing lug to drive it.

Just my ha'pennorth,
Dave H. (the other one)
 
Dave, Thanks for the step-by-step! I think I get it now..
Wes
 
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