Scraping Question

[graham-xrf]

If you know how much is taken off both the bed and the bottom of the saddle then depending on how the drive is (power cross feed or no?) then you could take that amount off the top of the apron and the lead screw should allign with the half nut. If you have power cross feed, then thing would get a bit more complicated, as raising the apron would effect gear meshing for the power cross feed. This will give you a bit to think about. Maybe a pro will come on here and let you know what they do in this situation. You might consider getting the book Machine Tool Reconditioning by Connelley, as it goes into a lot of detail on alignment.

Thanks for your reply. At least for the South Bend 9c, it being the least endowed, there is no power cross feed, which makes things simpler. I have the book, downloadable from this site in 6 chunks, and indeed it does address alignment. Scraping the ways has to involve removing unworn metal to get the new bearing surfaces below the worn parts, while at the same time progressing toward, or retaining alignment. It is a simultaneous process.
The book does not cover what to do about apron, cross-feeds, and suchlike other than to make the point that it is the main surfaces that are the priority. All other dependant slides, shafts and parts "can be moved".
Folk on this site have restored lathe beds, either by themselves, or by having them re-ground professionally. Therefore, they will have a list of consequential issues - things to be fixed. I think, maybe, what I am after might already be somewhere on this site.

 

[4GSR]

Graham,

If you don't find what you are looking for, let us know, many of us have vast knowledge of machine rebuilding/reconditioning experience! I myself have rebuilt several lathes over the years including my dad's 9" South Bend Lathe. Just let us know. Ken

 

[graham-xrf]

Graham,

If you don't find what you are looking for, let us know, many of us have vast knowledge of machine rebuilding/reconditioning experience! I myself have rebuilt several lathes over the years including my dad's 9" South Bend Lathe. Just let us know. Ken

Hi Ken
Many thanks. I am thinking there will come some point when I get in deep enough to need some pointers.
Right now, the first things are to get the drive arrangement up and running, and carefully start exploring.
I have a 600mm straight edge, magnetic base dial gauges (2), and various measuring kit (Mitutoyo, Kanon).
I guess that before long I might need a surface plate and a air compressor. Clean-up comes first, and that includes the clutter around it!

One question that comes to mind is.. does one start from the bottom and work up?
Put another way, can work to fix up (say) top parts like cross slide, compound, etc. be done independently of attending to the main ways?
It occurs to me that some efforts may be wasted, and parts have to be visited again if one tackles things in the wrong order.

What is the received wisdom about a tray underneath? This lathe is on a 1/4" welded steel plate bench top with a hole cut for the underneath belt drive. Not that I expect to be using lots of coolant. I just think a tray helps stop stuff from rolling off the back, and is easier to wipe up than the floor.

 

[eeler1]

To the OP, If its evenly worn over first 12", you could just make short parts.

 

[4GSR]

....snip.......
What is the received wisdom about a tray underneath? This lathe is on a 1/4" welded steel plate bench top with a hole cut for the underneath belt drive. Not that I expect to be using lots of coolant. I just think a tray helps stop stuff from rolling off the back, and is easier to wipe up than the floor.

I've seen all sorts of contraptions over the years to capturing shavings, oil, coolant. 1/4" plate sounds like a over kill to me but if it is working go for it.

 

[graham-xrf]

Perhaps I should have made it clear. The 1/4" plate is the top surface of the welded bench, made of 2" angle.
It is flat all the way to the edge. It has a hole under the headstock for the drive belt from underneath.
Already some bits rolled off the back. When I get this proper mounted to the concrete, it won't be so easy to retrieve stuff that made it off the back. Even if not a tray, maybe some sort of ledge stop around. Some wood strips?
I had thought a stainless tray, possibly rescued from the food industry, modified a bit, would be nicer.

Sorry - nearly off topic. This is early days. Be sure, I will be getting to some precision measuring/evaluation/restoration. My first scraping experiences so far have been confined to learning/practising on a pair of neglected V-blocks. Surface plate is 1" thick 6" diameter glass optical flat that suffered a small scratch near one edge, so dumped. Spotting is "Micrometer" brand Prussian Blue, though I found a 200ml tube of "Pebeo" brand red ochre oil colour from eBay works just as well, and has advantages in it's own way, and is much lower cost.