South Bend 9a Restoration (pic Heavy)

.................. If your tailstock end is not bolted down, get it bolt down and leveled good. Secondly of all the surfaces on your lathe to check the B and F in the above drawings are the only 2 surfaces that meant absolutely nothing. On war production machines this surface was not stoned polished or even scraped, they were simply planed. None of the carriage rides on this in any way shape or form so they are not a means of measuring the ways at all for wear.
To check for wear see if there is a ridge on the A,C, E or G surfaces, these would indicate wear and these are the only surfaces the carriage should ride on. If the carriage rides on B and F, the carriage itself is worn badly and not necessarily the ways.

Hate to bust your bubble, My dad's SBL has never had the tailstock end of the bed bolted down tight, ever! Always left loose. With this in mind, the bed ways are still in the same plane, dead straight and accurate, as it left the factory in 1949. It's never been leveled that I can recall all the years I've used it. I just recently checked the alignment with a "verfied" test bar. For a almost 70 year old lathe, it checked within 0.0010" in 6" in two planes 90 degrees from each other. Not bad for a lathe that South Bend called a "work shop" lathe.

And without the bed being put on a planer or way grinder to check wear, you always look for machined surfaces that are not worn. They don't have to be scraped, since the scraped portion of the ways started out planed surfaces, along with all the other parts of the bed, ALL in the same setup. Having said that, surfaces B and F as Dabber mentioned above can be used as reference surfaces for determining wear on bed ways. You don't use surfaces D, E, G, or H as Dabber has referenced. Those surfaces WILL have some sort of wear to them. And you don't use the tailstock ways neither. I've seen tailstock ways with just about as much wear as the carriage ways have.

Oh, I forgot to mention one other thing, South Bend Lathe only planed the beds smooth on the unhardened beds. They did not scrape them flat. They did lay very light flaking or frosting to the ways. This was the most common way lathe manufactures did the beds before the days of harden & ground bed ways. There were a few like Harlindge that did scrape their beds for super accuracy.

Ken
 
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Agree with everything said by everyone. But still doesn’t stop me from making a few comments. First, some brands DO wear on the “B” surface at the top of the V, Logan, for instance (I know this is a SB forum, but there’s been talk of other makes). Also, on the SB’s, as the ways wear, the B is no longer a flat, but becomes a ridge with vertical sides. If you can measure the vertical sides of the ridge, that could be a good indicator of how much wear there is on the ways, and also shouldn’t be uniform along the entire length. I don’t know how to do it but if you could.........

In that picture with the indicator, you don’t really need the indicator to see there’s quite a bit of wear, just look at the ridge. Just visually, looks like more than 0.010”. I’m wondering how the rest of the ways look at the tailstock end?

Another thing is that some owners or dealers may have worked over the B on an older, worn machine to make it look better for sale. So the B is a good reference only if it is unmolested.

This is a good thread.
 
It is possible but very unlikely that your lathe is that worn out unless it was used for years without lubrication.

--Here is how you measure your ways for a first check:

View attachment 251372
1) You need a good reliable test indicator or plunge indicator that has at lea st .0005 (half-thou) accuracy, and a magnetic base.
2) Your carriage should ride on ACH as per the diagram above.
3) Take a very fine stone (1000+ grit or hard Arkansas - 800 is used by some, but use it very lightly; I use a hard arkansas) that is lubricated and lightly dress surface B. The should be no wear on surface B, but it might have dings, and these will make the measuring miserable. You aren't trying to take a lot of metal off, but feeling that it is smooth without big raised areas. DO NOT ROCK THE STONE SO AS TO CUT INTO SURFACES A AND C...
4) CLEAN ABCD till it is spotless using rags and varsol, and lube them with light way oil.
5) Set your mag base on the carriage and position so you preload onto surface B - I've seen lots of guys indicate onto surface H and it doesn't tell you anything. B is not a wear surface, but H is.
6) Most every lathe maker surface grinds the B surface and on every SB9 I've seen it has been true.
7) Run your carriage back and forth slowly and note the readings. Now you know what you have. You can use this map of low spots (they show as High) to help you make very accurate diameters.
Ok to address the Leblond lathe, most all of the Regals I have run from the early to mid 1950's to present machines you simply removed the bed ways, measured them and bolt new ones on or have them reground, the vast majority of them have hardened tool steel removable ways, and sometimes the bottom of the carriage is hard chromed.

As to the South Bend, unless you have a flame hardened bed all of the ways were planed, only hard beds were ground, ask Ted Phleuger on the South Bend forum, he worked there for more than 30 years as a toolroom foreman.
Now as to how to check your bed for wear, there are several ways but B and F surfaces are not part of it. Here is one way and probably the best way that I know of, remove your head stock and mount an indicator on your carriage perpendicular to A, C , E, G and D and H if you like. Now run your carriage up on the surface that is unused under your headstock "0" out the indicator, now watching your indicator run it back down the lathe bed to the other end, this will show you where the wear spots are. Like I said one of the other ways is to look for a wear ridge on the top edge of A, C, E or G surfaces, In my experience the flat ways seem to normally wear on the tailstock bottom and not the bed, don't know why but all of the flat ways I have seen wear there rather than the bed. You can also use a straight edge perpendicular to the ways and see if you can get shims under it or there is a lot of light showing under it. If there is short wear spots this usually stands out rather easily. On the B surface only being about .090" wide, thats why I said look for a ridge on A and C surfaces, cause the slot in the carriage is about .150" wide so if there is a bit of wear it causes a ridge on the sides of the V way a sit wears and settles lower on the ways.

This is a good thread.

This is a good thread. Thanks
LK
 
I think if you took material off the spindle and off the bearing you might have too much clearance. Also, either one could now be out of round. i think the proper way to repair this is to get the spindle precision ground at a machine shop. Not a big deal at all. I was once told that no shop foreman ever turned down cold hard cash and that has been my experience. Just walk in with your part. You want it ground on a cylindrical grinder, just enough to clean it up. Then you want to machine a new bearing insert (of course you need a lathe for that) and internally grind it and lap it to size. Then your spindle will be perfect. While the lathe looks really pretty because of the new paint, it is rebuilding the mechanics that will make it into a like-new machine. Scraping the ways and getting rid of play in the bearings is what really counts. If everything is badly worn you will still be frustrated after all that clean up work. Been there, done that.
 
I think if you took material off the spindle and off the bearing you might have too much clearance. Also, either one could now be out of round.

Thanks. The spindle was tested and shown to be well within spec after the work was completed. I've had no issues from the spindle after 1+ year of use post rebuild.
 
Anyone using polishing compound like this make sure that you Clean clean clean.....
Polishing compound is very abrasive and it will keep cutting away....
 
I don't know what to say. Amazing. Beautiful. Inspiring. Nice work seems underwhelming.
 
Would you happen to still have the restoration book? Is it on a pdf at all? I have a 9a not sure the year but would not mind doing some cleaning to it one day.
 
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