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The Artful Bodger
03-25-2011, 01:10 AM
Sorry about the typo in the title!

My little Adept lathe as received:-

http://farm6.static.flickr.com/5176/5511632818_2a20e1e634.jpg (http://www.flickr.com/photos/25239206@N06/5511632818/)
DSCN0294 (http://www.flickr.com/photos/25239206@N06/5511632818/) by aardvark_akubra (http://www.flickr.com/people/25239206@N06/), on Flickr
It looks good but the bearing in the head are really, really slack.


The bearings are simply borings in the casting so with nothing to loose I tried a little bodge, just because I could!
http://farm6.static.flickr.com/5065/5557881172_ec27fb3757.jpg (http://www.flickr.com/photos/25239206@N06/5557881172/)
IMGP9177 (http://www.flickr.com/photos/25239206@N06/5557881172/) by aardvark_akubra (http://www.flickr.com/people/25239206@N06/), on Flickr
First off strip the lathe (that took 45 seconds!) then clean the head bearings and heat with the heat gun.




Now I am putting solder in the bearings. http://farm6.static.flickr.com/5097/5557296603_afc2e27d81.jpg (http://www.flickr.com/photos/25239206@N06/5557296603/)
IMGP9178 (http://www.flickr.com/photos/25239206@N06/5557296603/) by aardvark_akubra (http://www.flickr.com/people/25239206@N06/), on Flickr
You might have heard that cast iron cant be soldered, well, it cant be soldered easily but it can be done and one of the methods is to rub the surface with copper while applying the solder. While the heat guns keeps the metal hot I added solder via a little soldering iron giving the surface a generous rub as I did so. Eventually most of the bores showed solder adhering to them. Sorry, no picture of that my camera is not good enough to 'see' inside there.

The Artful Bodger
03-25-2011, 01:11 AM
Now I am going to trim the inside of the bores, I realised the drill was not going to be such a good idea and eventually carefully trimmed it out by hand.
http://farm6.static.flickr.com/5024/5557296685_8f982273f7.jpg (http://www.flickr.com/photos/25239206@N06/5557296685/)
IMGP9179 (http://www.flickr.com/photos/25239206@N06/5557296685/) by aardvark_akubra (http://www.flickr.com/people/25239206@N06/), on Flickr

The bores felt 'good' but not perfect, so I made up a rig to give the little lathe a try out!
http://farm6.static.flickr.com/5228/5557881030_36815ce72a.jpg (http://www.flickr.com/photos/25239206@N06/5557881030/)
IMGP9191 (http://www.flickr.com/photos/25239206@N06/5557881030/) by aardvark_akubra (http://www.flickr.com/people/25239206@N06/), on Flickr


There we have it folks, a little tapered pin turned up on this tiny lathe!
http://farm6.static.flickr.com/5292/5557296795_dd33b8e545.jpg (http://www.flickr.com/photos/25239206@N06/5557296795/)
IMGP9193 (http://www.flickr.com/photos/25239206@N06/5557296795/) by aardvark_akubra (http://www.flickr.com/people/25239206@N06/), on Flickr


Now I need to know how to carefully bore out the headstock to take bushes of some kind. I have what I think are 'oilite' bushes, they are bronzy looking and have a distinctly oily look about them. Any comments on using these bushes anyone?

PeteF
03-25-2011, 01:26 AM
I'm not sure how long the solder will last in there.

There's a series of somebody line boring a plain bearing SB9 and fitting bushings to it. That may give you some ideas anyway. I think it was on PM IIRC

Pete

Edit: Found it! Not sure, but may be helpful http://www.practicalmachinist.com/vb/south-bend-lathes/fitting-bronze-sleeves-9-headstock-146690/

Black_Moons
03-25-2011, 01:39 AM
the casting has a split and a bolt in it, Isent that for tightening the bearings?

The Artful Bodger
03-25-2011, 01:42 AM
the casting has a split and a bolt in it, Isent that for tightening the bearings?

Yes, but on this type of lathe tightening those down is very likely to snap the casting. That has already been done by someone in the past and a brazed repair.

Forrest Addy
03-25-2011, 01:52 AM
Some potable water solders make a fair substitute for Babbitt metal. It ain't perfect but it's acceptable.

darryl
03-25-2011, 02:00 AM
Since the original bearings are just bored in the cast, your options are to bore them out large enough for a thin-walled bushing, or maybe you can get away with a two piece clamshell bearing, which I think should let you get away with the least amount of 'over boring'. I wonder if you can buy babbit in sheet form and roll your own to fit- or some other suitable sheet material such as silver (only partially kidding about this). Oilite is pre-oiled of course, so you wouldn't have to lube as often, but with any bearing shell material you'd have to supply constant lubing.

If you set up a constant lube system, you could even use aluminum for the bearing shells. Maybe check out what used to be done in aero engines as far as bearing material.

My motorcycle has steel shafts running directly in machined aluminum bores, and I think a lot of them were like that.

Another thing to consider is a hydrodynamic type of bearing, where the lube circulates by virtue of the shaft turning. Many hard drives these days are made with this type of bearing. I have one in front of me right now, apart, and I can spin the disc with my fingers. Spin it one way, it glides along for a bit before it stops. Spin it the other way, it doesn't want to go. Shaft rotation forces an oil wedge to form and keeps the shaft from direct contact with the bearing material. If you rolled your own shells, you could create the oil grooves beforehand to create this action. Miniature ball bearings are so cheap these days that they would be used exclusively for hard drives, except they don't run as smoothly as plain bearings with this oil-wedge technology.

I think this is well worth looking into, since with some care you can make these at home. What are the bearing surfaces on the spindle like- in good shape or ?

As far as boring what you have, and in a perfect alignment, I'd be tempted to use the tailstock to control one end of a straight shaft and the inboard headstock bearing to control the other end. Careful measuring, and using the carriage should be able to tell you whether the shaft being held this way is parallel- on other words if you actually turned diameters on it, would they show a taper or not. If you can get an alignment on the tailstock to make this true, then the shaft can be held in perfect position to bore out the left end bearing. This would be a lot of fooling around to get to be able to re-size both bores, but I think it could be done.

Another way might be to make two identical holders that fit the ways, each being bored with tooling in the chuck (the lathe would have to be usable for this operation). If both holders are machined in the same spot on the bed, their bores should line up exactly parallel to the spindle axis. They may not be exactly on axis, but they should be parallel. Then they can be used to carry a straight shaft which would carry a boring bit on the end of it, micro-adjustable of course. With either of these scenarios, you'd have to motorize the shaft to spin the boring bit, plus be able to move the shaft along in a well controlled manner.

Just throwing some thoughts out there.

franco
03-25-2011, 02:13 AM
Bodger,

QUOTE: "Now I need to know how to carefully bore out the headstock to take bushes of some kind."

The easiest way if the height of the Adept spindle will permit it is to mount the Adept on the cross slide of your bigger lathe and use a between centres boring bar - a smaller version of the set-up shown in the third photo here:
http://www.lathes.co.uk/drummond/page3.html

The workpiece is fed over the boring bar using the lathe's normal power feed.

Even with the small diameter of the boring bar which would be required you can get quite good results using light cuts. You would have to work out some system of measuring the amount of tool stick-out from the boring bar to adjust for each cut - often done using a dial indicator mounted on a suitable bracket. Note that the boring bar effective overall length will have to be double the distance between the outer ends of the headstock bearings, and the tool in the middle of the bar.

Alternatively, if you have a boring head which can be mounted in the headstock spindle, this will work too.

An interesting variation of this is described by electrosteam in post #4 here:
http://www.woodworkforums.com/f65/using-between-centres-boring-bar-129635/

where he says:

QUOTE: "Recently, cannot remember where, I saw reference to a between centres boring bar with a boring head in the spindle holding the headstock end of the boring bar.

The boring head is set on centre initially, the job rough bored with normal tool adjustment on the boring bar, then the boring head adjusted for fine tool trimming.
With a good boring head, you can dial-up the required amount of cut.

The headstock end of the boring bar moves in an orbital motion, but still circular."

Since the tool is in the middle of the boring bar, the amount of tool movement would be about half the amount of offset applied to rhe boring head.

franco

The Artful Bodger
03-25-2011, 02:35 AM
Darryl, the most easily available sheet materials are brass and copper, are either of these suitable as a bearing material?

The spindle is a simple 3/8" shaft and appears in good condition, obviously it would be easy enough to make another of these. The one I have is not original which would have had a Morse taper.

One of my options is to bore for a larger diameter spindle, a 10mm spindle is only .475mm oversize so thats one fairly easy option and might be good for another 60 years!

Thanks for the pointer to hydrodynamic bearings as that looks quite interesting even if I dont wind up using it for this project.

Alignment is a concern for boring and your idea of the two holders is a good one, fortunately the tail stock has the same bore as the head stock so thats could be useful. What will be difficult for boring is getting the bored size right as 3/8" is rather small to my mind!

Thanks for your comments and advice.

The Artful Bodger
03-25-2011, 02:39 AM
Thanks Franco, that 'orbital' boring bar is an interesting concept. I will have to think how I could use that.

macona
03-25-2011, 02:41 AM
Copper, bad bearing material. Brass, so-so.

I would bore and hone to the 10mm like you said. And get some TGP rod for the spindle. The Artisan lathe I have uses plain bearing. Steel running on cast iron. Works fine.

RussZHC
03-25-2011, 07:26 AM
Oilite: the only thing I have read about this, in the "take care" department, is to use really sharp tooling as you don't want to "smear" the surface. Supposedly "smearing" can effect the movement of the oil (has to do with the porosity of the material)

RayV
03-25-2011, 08:23 AM
I have a couple of older lathes that have Oilite Flanged bushings on the spindles and they work fine. They have oil cups over each one and I oil those areas every time I use them.

Ray

J Tiers
03-25-2011, 08:50 AM
Artful........

I don't know about over there, but in the US, leaded solders are illegal for water pipe usage (we use a lot of copper pipe).

As Forrest mentions, for water pipe in the US there are considerably harder solders which are tin with silver and antimony (yeah, don't ask). I have successfully used them as a "babbit" material.

Dunno who told you that CI can't be soldered, but they didn't know very much, must be a "book larnin only" type....... I've soldered to CI with soft and also water-pipe solders, it works fine if any oil is burned out of the iron first....

aboard_epsilon
03-25-2011, 10:16 AM
Have a Super Adept that was given to me by the guy across the road ..

Spindle bearings are trashed because he ran it with a 6000 rpm motor and no countershaft .

must have buggered those spindle bearings up in ten Min's ..

Th rest of the lathe has only had ten Min's use !!!!!..its as new with no wear on any other part.

was trying to figure out weather i could sell it ..on ebay in this condition ..
weather it would be better to sort it out and fix the bearing problem
and sell on ebay

or to make a countershaft for it ..get a another motor ..and sell it on ebay ..

see that "Th" up there...i cant correct it ..without words moving up against it ..this happens frequently in this forum ..no other

anyone know how to sort this word shuffle out ..makes me look crap


all the best.markj

Black_Moons
03-25-2011, 01:40 PM
Artful........
As Forrest mentions, for water pipe in the US there are considerably harder solders which are tin with silver and antimony (yeah, don't ask). I have successfully used them as a "babbit" material.


I recently bought some 56% silver braze, And I highly believe that silver is indeed 'Antimoney'

(Okok, Bad pun)

Toolguy
03-25-2011, 02:39 PM
I would bore out the holes and make headed bushings out of Delrin. Once installed with a slight press fit, ream to size with an adjustable hand reamer. Then drill oil holes down through the top to add a bit of oil once in a while. That setup should run for a long time.

sasquatch
03-25-2011, 07:36 PM
What a sweet little lathe!!!
Thanks for posting the pics!!

J. Randall
03-26-2011, 12:03 AM
Oilite: the only thing I have read about this, in the "take care" department, is to use really sharp tooling as you don't want to "smear" the surface. Supposedly "smearing" can effect the movement of the oil (has to do with the porosity of the material)

Russ, I have read that also numerous times, but I have bored Oilite with a sharp tool, cleaned it up and filled with oil, and pressed with thumb and finger on the ends, and watched the oil ooze out of it just like before. Maybe you could smear it enough to matter, but I never have.
James

darryl
03-26-2011, 03:07 AM
I've bored a few oilite bushings- not lots but some. I find that you need a sharp tool with good clearance and rake angles to avoid smearing the metal and closing up a lot of the pores. That is, if you want to keep the original degree of porosity and oil availability to the shaft.

What I came to feel is better is to bore the housing a precise size that allows for the press fit to shrink the bushing to the desired ID. Of course to do this you play a game of finding appropriate sizes, and either trusting the math or experimenting with fits to get to the desired result.

If you're going to press a bushing into a modified bore, you may have no choice except to bore afterwards to get the precision required.

That is a cute little lathe. Reminds me of my Unimat project- I've got a cast bed with dovetail ways on it that I'll mount the Unimat headstock on, keeping the angle capability for taper turning, and replacing the carriage, etc with a more solid setup similar to larger lathes.

S_J_H
03-26-2011, 04:19 AM
There's a series of somebody line boring a plain bearing SB9 and fitting bushings to it. That may give you some ideas anyway. I think it was on PM IIRC

Pete

Edit: Found it! Not sure, but may be helpful http://www.practicalmachinist.com/vb/south-bend-lathes/fitting-bronze-sleeves-9-headstock-146690/

That would be me. :)

The project was also covered in this forum-
http://bbs.homeshopmachinist.net/showthread.php?t=26578

Well I used 660 bronze for my sleeve inserts. I have well over 1000 hours on the lathe now and the inserts show absolutely no wear. I run the clearance at .0007" at each end. The pics show the type of oil groove I made.

Delrin would probably work in the little headstock. I find bronze easier to machine to a exact diameter than delrin though.
As a bit of a coincidence I began line boring and sleeving the tailstock on that SB today.
I am going to use Delrin for the sleeve.
Steve

PeteF
03-26-2011, 05:53 AM
Steve boring a tailstock is often discussed here, so any chance you can take the time to document the process on a thread?

Pete

Boostinjdm
03-26-2011, 07:01 AM
I figured I'd throw in my $.02.

Shim up your clamping slits. Ream for oil-lite or similar bushing. Loosen clamping screws and install bushing. Tighten screws and ream bushing to align bores. Make spindle to fit. That last reamer can also be used on the pulleys to make them fit the new spindle. That's just how I'd do it. Or maybe I'd just ream the original bores to clean them up and make a spindle to fit. Why over complicate things?

Black_Moons
03-26-2011, 07:40 AM
I would likey just bore it oversized and make a new spindle then.

Maybe insert oilite bushings if you really wanna be fancy. I would'nt use derlin because a small lathe will want to be operated at a very high RPM.

RussZHC
03-26-2011, 11:34 AM
:D :D :D :D

Very glad this thread came up.

THANKS S J H

I am finally a bit encouraged that the old Sheldon project will work out.

S_J_H
03-26-2011, 02:12 PM
Steve boring a tailstock is often discussed here, so any chance you can take the time to document the process on a thread?

Sure, I'm also converting it to a lever feed with a new ram. I'll post a thread when it's finished.
Steve

loose nut
03-26-2011, 08:18 PM
You can get brazing rod that is used for making "brazed in place" bearings. Braze the holes up full and bore them out.