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Paul Alciatore
11-15-2004, 01:36 AM
I am toying with the idea of making a steady rest for my SB9. The prices on E-Bay have driven me to it.

So I am sketching to find a good geometry and a question pops up. Some of the steadys I have seen have screw adjustments for setting the fingers and some do not. What are the advantages and disadvantages of having screw adjustments?

Also, what is the best material for the fingers, or at least for the tips that rub against the work? Brass? Bronze? What?

Paul A.

CCWKen
11-15-2004, 01:50 AM
Brass works good. If you use it a lot on threads, make a couple of extra tip sets. The screw type are faster to adjust. All you do is loosen a knurled locknut and turn the knob in or out and re-lock. No fiddling with a wrench that pulls the finger out of adjustment.

Does the SB-9 bed have a single V and a flat? How wide? I may have a casting. It only has one screw assembly but it's enough to give you a pattern to make the other two. I'll measure it and get back tomorrow.

If it fits, it's yours for shipping.

Forrest Addy
11-15-2004, 01:53 AM
There's no particular geometry that works the best on a steady rest. Three roughly radial jaws spaced as convenient is all that's required. The upper half should be well fitted on its hing pin and clamping surface so there's no slack.

For smaller lathes where the steady jaws are tiny and almost weightless not adjustment screw is really required. Just touch the jaw agianst the work and tighten the clamp.

As for jaws, use bearing bronze if you can get it. Otherwise cast iron, brass, whatever will work fin.

I know a guy who swears by the potable water solder (96 tin, 4 antimony) he lines his steady jaw tips with. He just solders on a big blob, dresses it a little to conform to the work, and goes to town.

Mike Burdick
11-15-2004, 02:00 AM
Paul,

This isn’t answering any of the questions you asked but you might try an alternative to the “typical” steady rest. Use a large diameter ball bearing and press fit a sleeve into the center that has four (or three) bolts tapped into it so you can hold the work piece. Basically this is what is called a cathead. The ball bearing is held in a holder that resembles the “typical” steady rest so it can be moved along the ways as normal. Using this, one doesn’t have to worry about the fingers marring the work piece, lubrication, or even shape of work. For the bearing, go to the Caterpillar repair shops and they may have something in their dumpster for free. If you like it and need more accuracy, then you can buy a class 7 bearing later.

John Stevenson made one and has a picture of it somewhere. I think it’s in the “Sharing Tips” thread and I would post a link to it but I have a dial up connection and it takes too long for me to load the thread because of the numerous pictures. Maybe someone else can find it and post a link for you.

Anyway you might consider this since it’s easy to build.

-Mike


Oh, I found them!

http://homepage.ntlworld.com/stevenson.engineers/lsteve/files/Steady2.jpg
http://homepage.ntlworld.com/stevenson.engineers/lsteve/files/Steady3.jpg
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[This message has been edited by Mike Burdick (edited 11-15-2004).]

JRouche
11-15-2004, 04:17 AM
Cross posted:

My S.B. 10" has brass fingers. I have two sets, one has the standard brass tips the other I fitted with roller bearings.

The screw feed is quicker to set up the work because you can make fine adjustments while dialing in the piece. With the other type you would have to release the locking screw, push the finger towards the work with the end screw, lock the locking screw then take another measurement. With the screw type fingers you can dial it in on the fly while the work is rotating. JRouche

wierdscience
11-15-2004, 09:47 AM
If you decide to go with roller tips,then whatever you do use square or rectangular fingers fitted into slides.The round keywayed fingers suck,they contain too much slop in the keyway and allow the roller to cock slightly askew which will roll a groove in the workpiece.
For soft metal tips,bronze or babbit is what I prefer.

snowman
11-15-2004, 10:47 AM
The bearing system brings up a question I've had for a while. It has four adjustment screws...the average steady rest has three fingers. It seems that four would be easier to dial in than three...

Why do most standard steady's have three?

-Jacob

[This message has been edited by snowman (edited 11-15-2004).]

kap pullen
11-15-2004, 11:52 AM
The really big lathes have steady's that have clamp bolts front and back.
They omit that pin joint compleatly.

That way you only have to mill the faces flat front and back, tap the bottom and drill the top half.

Take care laying out the finger slots or holes.

If the slots or holes are off position they ain't gonna meet in the center and small work will not be possible.

If you have room. fit little ball bearings, or cam followers in the fingers.

I have made several rests over the years and the ones with hard bronze, or ball/roller bearings seem to work the best.

Don't try plastic tips because they get hot, expand, and lock up.

Kap

gundog
11-15-2004, 01:16 PM
I have been thinking of making a steady with a bearing Like John's but using a four jaw chuck. This would be used for gun barrel work because my lathes spindle bore is too small. What do you guys think, would that be too much weight to start spinning? My lathe is a SB 10K.
Mike

Paul Alciatore
11-15-2004, 02:23 PM
Interesting ideas here. Now I want two, a standard steady and one of the cathead, BB types.

I could be wrong but I suspect that the three finger arrangement is: a) the minimum that will work, b) for economy, c) the three finger style puts a finger at the top where it can best support against the lifting force created by cutting, and d) because it is harder to locate four FIXED location adjustments so that all can be easily reached. The lower rear one would be about 15* lower with a four finger arrangement. If I were making a four finger steady, I would definitely want one of them within 15* of the top center. But then the bottom one would be arkward.

But four points make a lot of sense in the cathead.

Oh, and I think I will consider the roller tips also. But if I use rectangular fingers, how would you add a screw adjustment to them?

Anybody got any tips on boring the hole for the cathead rig? Perhaps I can rig for the carriage to push it into a boring tool mounted between centers while it slides on the ways?

Lots of questions here.

Thanks all. As always the response is just great.

Paul A.

John Garner
11-15-2004, 04:16 PM
Paul --

A now-retired coworker made both a center and follow rest "in the solid" and was very happy with the results. He cut the bodies of the rests from aluminum plate, fitting one to the ways and the other to the saddle, and bored good-sized holes through the bodies using a boring head in the headstock.

Instead of adjusting "fingers", he made bushings with ODs a close slip fit in the rest bodies, IDs as necessary to the job at hand.

The follow rest was set up so that it could also hold toolbits on both the headstock and tailstock sides.

John

John Foster
11-15-2004, 05:11 PM
I mounted 3 alternator bearings on the cast iron fingers that came with my SB steady. Works great and the few times I want the original fingers, loosen the 3 screws and the bearings are off.

wierdscience
11-15-2004, 08:34 PM
Maybe this will give you some more ideas-
http://img.photobucket.com/albums/0903/wierdscience/STEADY.jpg

This is one I started building for my lathe at home.I started out by burning and turning out a steel ring from 1"plate,it has a 1 x 2-1/2" crossection.I turned it out and then made two blocks from 1 x 2" flatbar and milled a vee-notch in them.
To lay out the slides,I just chucked it up it the three jaw and used a straight edge and scribe to transfer the locations using the chuck jaws for reference.Once I had them milled I returned it to the chuck,brought the top slot up vertical and then clamped the two vee-notched blocks one on each side with heavy clamps.Then I just took the whole mess out of the lathe(carefully)and welded the blocks to the ring.I only had to make a couple of passes with a file to get the vees to seat solidly to the ways.
It's gotten rusty hanging on the wall while I am modifying my lathe.Hope to finish it and the lathe this winter.

dkinzer
11-20-2004, 05:20 PM
I have scanned a Pop Mech article from 1956 that shows one simple way to make a steady. It uses bronze bolts for the fingers.

You'll find it at the bottom of this page.
http://www.kinzers.com/don/MachineTools/lathe_projects

Another option is to get the casting kit from Metal Lathe Accessories:
http://www.sc-c.com/metallathe/MLA-9.html

lugnut
11-20-2004, 11:45 PM
There is a guy that has posted a plan and drawings for a steadyrest and a bunch of other usefull items for the home machinist. He is well worth looking at. His site is : http://homepage3.nifty.com/amigos/index-e.html
I have started making a couple of his items.
hope this helps
Mel

MikeHenry
11-21-2004, 11:23 AM
Paul,

Have you looked at the MLA steady rest casting kit? It's designed for a SB9, I think, and runs around $60 plus shipping.

http://www.statecollegecentral.com/metallathe/MLA-9.html

Mike