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South Bend 9a Restoration (pic Heavy)

RandyM

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#92
Damn, I did not see that.
Yep, I guess he had no choice
It is easy to miss the details sometimes. I have to go back and re-read post all the time. Actually, he had a second option and that was to make the tray bigger to include both legs. All in all, he did a great job.
 

wildo

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#93
Very nice work! Like fine sculpture. But it isn't a lathe until there are chips and cutting oil in the chip pan...;)
There's a whole lot more than that under there! Been doing a lot of cast iron work lately. Now that's some dirty stuff. I need to take more time to clean up, honestly... It might seem ludicrous, but the process of keeping a machine shop clean is completely foreign to me. As in- I entirely don't get it. There's chips and cutting oil all over EVERYTHING. I watch the likes of Adam Booth, Keith Fenner, Stefen Gottenswinter, and all the other "big name" guys on youtube and I honestly don't understand how they keep their shop so clean. I would find a video on "machine shop cleaning" to be highly informative. Then again, I am a thirty something bachelor, so there is that...
 

wildo

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#94
Thanks Gents! I appreciate the comments. Admittedly, a lot of what I did on this restoration was NOT a result of understanding or experience, but rather in simple guesswork about how to go about things. As I mentioned (somewhere- maybe here, maybe in another thread) I've been building stuff and making stuff my whole life. Even so, I find machining to be a considerable new challenge. I mounted the chip pan as I did for two reasons:
  1. It mimicked how the chip pan is mounted on the SB Heavy 10 when on the pedestal base, and
  2. Because it mimicked that look- I thought it looked cool.

Given the amount of oil that seems to be constantly on my bench under the gear box, I might have approached this differently with this new information. Perhaps offsetting it such that the headstock end sat in the oil pan and the tailstock end was not in the oil pan might have been a better way to go. I do think it would have looked rather wonky in spite of "form follows function."
Either way, it all seems to be working out just fine. The lathe is working well, though I'm finding the .008" of wear near the headstock so debilitating that I'm saving up for a new PM 1228VF-LB. Sure, it sucks to walk away from the old iron, but old iron is only good if it's functional. And for the precision work I'm trying to do with spinning tops (ten-thou tolerances) it's REALLY hard when I can travel ONE INCH and get .008" taper.
 

4gsr

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#95
Oops, you posted before I had a chance to post. You may disregard what I've said here, sorry. Ken

It's just like the house you live in. Same cleaning procedures apply to the house apply to the shop! Oh, you're a bachelor, cleaning? never!:(

That will change if you ever get married!

Rule number one, when your done working in the shop for the day, sweep the floor! So that way the shavings don't get tracked into the shop.
Number two, learn to clean and oil your machines. Wipe down your machines! Bounty paper towels work good for this. When you wahs your hands, wipe off with Bounty paper towels. Lay the paper towels out to dry. Now they go to the shop for use out there.

Ken
 

wildo

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#96
It's just like the house you live in. Same cleaning procedures apply to the house apply to the shop! Oh, you're a bachelor, cleaning? never!:(

That will change if you ever get married!
You hit the nail on the head here, Ken! LMAO!!!!
 

Bob Korves

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#97
And for the precision work I'm trying to do with spinning tops (ten-thou tolerances) it's REALLY hard when I can travel ONE INCH and get .008" taper.
Willy, .008" in 1" taper is not likely from the ways. You have some other issue going on there. It could be the headstock mounting, the tailstock offset (if you were cutting between centers), a carriage that has slack in the mounting, a tool post not properly mounted, or other issues.

Start here, chapter 26:
http://www.hobby-machinist.com/threads/connelly-on-machine-tool-reconditioning.41802/
 

wildo

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#98
Willy, .008" in 1" taper is not likely from the ways. You have some other issue going on there. It could be the headstock mounting, the tailstock offset (if you were cutting between centers), a carriage that has slack in the mounting, a tool post not properly mounted, or other issues.

Start here, chapter 26:
http://www.hobby-machinist.com/threads/connelly-on-machine-tool-reconditioning.41802/
There probably are some other issues in play, no question, but if I have a Bison 6" chuck on (so I'm working a good 6" away from the headstock) I only get about .001" taper across an inch. When I move to a collet, which I've been doing a lot of lately, it puts the carriage right over the worst part of the way wear and I get really considerate taper.
 

Dabbler

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#99
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:


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.

My guess, sight unseen, is that you have other alignment issues, but if your carriage does drop .009 then the restoration is gonna take TIME and a LOT of it.

I've seen 5 or 6 SB9 lathes in my time, most of them heavily used from schools (where they were abused) and I've seen max .003 wear in the carriage tracking. It is usually more like .001. Using good techniques, you can still turn a shaft to .001 diameter on one worn to .003 on the indicator. It just takes time and being very picky (and the lathe properly set up). If you buy a PM 1228VF-LB (ort even a Hardinge) and don't use a lot of care, you won't be able to turn and hold .001 accuracy, let alone .0001. It takes a lot of experience to turn to .001

FOR THOSE WHO WOULD OFFER ALTERNATE MEASUREMENTS: (my apologies)
Yes, I know this isn't definitive, just a first quick check for wear. There are a bunch of checks in Connely's book, but it may be the lathe is very good! - I'm in love with the old iron!

P.S. I just helped check a Standard Modern lathe that was used in a school for 35 years and crashed dozens of times: the ways were worn less than .005 (oops - make that .0005, that is, 1/2 thou) using my Mitutoyo .0001 test indicator.
 
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wildo

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I've seen 5 or 6 SB9 lathes in my time, most of them heavily used from schools (where they were abused) and I've seen max .003 wear in the carriage tracking.
Thanks Dabbler for the detailed wear measurement instructions! I just did a quick test using the instructions you indicated above. Please forgive the really dirty lathe; I just wrapped up a cast iron/bronze job. But I cleaned down the lathe ways, lightly stoned the "B" surface you indicated, and took a measurement. A bit more than you expected, eh?

 

Dabbler

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I've never personally seen wear like that - I have *heard* it is possible, but oh my gosh! You can't hold to good tolerances with that much wear - so your idea of a PM lathe seems like a good approach.

Because I live in an oil town, we have several very large grinders that can grind the ways back to tolerance, but such a job is in the $1000 range, even here. Then you have an old lathe with old bearings, cross slide wear, etc. A machine that badly abused (by not oiling the ways) isn't worth the cost of making it 'right'. Selling it for a start on a better lathe sounds about right.
 

wildo

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...but such a job is in the $1000 range, even here.
Unfortunately, I'm no longer certain that I can swing the cost of the PM lathe. At this point, a $1K regrind job is a fifth the price of a new lathe- and that I'd be willing to pay. As a hobbyist, I can't imagine I'd inflict too much damage over the course of my life on newly ground ways (assuming proper lubrication). So it really would make this an heirloom piece.

I have sent messages out to a few companies; waiting to hear back. One company responded that they would be happy to sell me a $16K Lagun instead. :)

"I wish we could help, but these machines are not feasible to rebuild. Replacements are too cheap. We can sell you a Republic Lagun lathe for $16K that is less than the rebuild cost. Although they are small, it take the same amount of steps and setups as a larger machines. Actually, the small one are harder to do. We thank you for the inquiry and ask to keep us in mind with other machines."
 

Dabbler

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Wildo, perhaps you can find one of the more experienced members near you and go together to look at used lathes. If you are patient, you can find excellent buys on the used market. In some places in the U.S, you can find good lathes for about the cost of a grinding job. One of the guys here bought a 11X20 Standard Modern lathe in near perfect condition (out of a school) for 1300 Canadian pesos. (- is that about $2.70 in American?)

Take heart a great lathe is out there - and in the mean time, you an start on your current one!
 

woodchucker

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I paid $250 for my SB 9a. It required a complete rebuild. But was well worth it. These days I wish I had a bigger machine as far as spindle throat size, and 5c capabililty.
but a 9A in decent shape is in you future. if you are willing to travel a little maybe 2 hours, I'll bet they are plentiful.