It's possible that the vendor messed up the quote or I wasn't specific enough; however I did give them the part numbers directly from the manual. Regardless, I think I will pay them a visit and see what the deal is.
Standard Modern 11" Series 2000 Lathe Spindle Issue
- Thread starter Crosche
- Start date
It's possible that the vendor messed up the quote or I wasn't specific enough; however I did give them the part numbers directly from the manual. Regardless, I think I will pay them a visit and see what the deal is.
Tom Kitta
Ultra Member
I have some Timken bearings - l have cups and actual bearing - they are quite large. I think through they are automotive precision.
https://cad.timken.com/item/all-pro...d-single-with-flange-imperial/68462-68712-b-2
and
https://cad.timken.com/item/tapered...-roller-bearings---single-cups---imperial/672
I think they are way to large for you.
In case you want specifics size go to eBay - you can find stuff there that is *much cheaper* then from supplier.
You are very lucky you can get bearings for your lathe that are still in production. However ABEC 3 bearings that are not widely available will cost indeed a lot of money - even if still made.
Sizes in 4inch bore and 6" outside are for under 200 USD on eBay - but I think it is automotive grade ABEC 1 or something like that. Check your size.
Before you buy make sure your bearings are indeed dead - it is not exactly "quick procedure" in many lathes to change bearings. Also pre load frequently is a mystery and determined by how much stuff moves.
https://cad.timken.com/item/all-pro...d-single-with-flange-imperial/68462-68712-b-2
and
https://cad.timken.com/item/tapered...-roller-bearings---single-cups---imperial/672
I think they are way to large for you.
In case you want specifics size go to eBay - you can find stuff there that is *much cheaper* then from supplier.
You are very lucky you can get bearings for your lathe that are still in production. However ABEC 3 bearings that are not widely available will cost indeed a lot of money - even if still made.
Sizes in 4inch bore and 6" outside are for under 200 USD on eBay - but I think it is automotive grade ABEC 1 or something like that. Check your size.
Before you buy make sure your bearings are indeed dead - it is not exactly "quick procedure" in many lathes to change bearings. Also pre load frequently is a mystery and determined by how much stuff moves.
Dabbler
ersatz engineer
So @Crosche and I spent a while doing all kinds of measurements... Yes his spindle is bent, but not irretrievably. the inner taper MT#4, was about a half tenth out, which is fine for lathe that old and used... the taper of the D1-4 is out about .002 and the outer flange consistently clocks at .005 out in axial measurement. The face seat of the d1-4 is so rough, that a half thou indicator couldn't read it.
None of this is fatal, and a tool post grinder can clean up the axial runout. The radial runout is still just fine.
His new Shars chuck seats on the area near the taper, so we adjusted it and got it fitting quite nicely.
For the sad news, his 3 jaw chuck, a very high quality Pratt chuck BTW, will probably have to be replaced. as the taper seat is badly chowdered.
None of this is fatal, and a tool post grinder can clean up the axial runout. The radial runout is still just fine.
His new Shars chuck seats on the area near the taper, so we adjusted it and got it fitting quite nicely.
For the sad news, his 3 jaw chuck, a very high quality Pratt chuck BTW, will probably have to be replaced. as the taper seat is badly chowdered.
Thanks for bringing us up to date Dabbler. It was very nice of you to help out a fellow hobbiest. Are you guys going to grind the face of the spindle? That would make a great video for those of us who have never seen it done.
Firstly, Dabbler, you have my sincerest gratitude for taking the time to inspect my lathe and educate me at the same time; especially in light of the current pandemic situation. My shop, my equipment and my skills; as modest as they may be; are at your service and in your debt.
As far as the lathe is concerned, I am not sure whether to be happy that it's not the bearings that are the problem or not, but I will have to correct the problem at hand and I see post grinding the D1-4 spindle nose in my near future. I will try to get video footage or at least good pictures of the set-up and process when it happens.
With respect to the bearings, @RobinHood and others who may be interested. I contacted Standard Modern for a quote for the main bearings for my lathe and specifically asked for the bearings that they use and I was quoted $300 for the assembly, so I can only assume that the bearings they use are C-2's and the same as quoted by TPL. In my research regarding the bearings I did stumble across C-3 bearings in stock for $770 USD ($1100 CDN) which is slightly more palatable than $1500 CDN and 6 month lead time provided by Motion Canada. https://3bgsupply.com/bearings/roller-bearing/387a-3-timken
Lastly, I want to thank all of you who offered up advice, observations and encouragement. I was very concerned that I made a poor purchase and was going to be stuck with a lemon who's cost to repair would far outweigh it's actual value but with your help I have a clear path forward to grind / polish this "turd" into something I can be proud of.
As far as the lathe is concerned, I am not sure whether to be happy that it's not the bearings that are the problem or not, but I will have to correct the problem at hand and I see post grinding the D1-4 spindle nose in my near future. I will try to get video footage or at least good pictures of the set-up and process when it happens.
With respect to the bearings, @RobinHood and others who may be interested. I contacted Standard Modern for a quote for the main bearings for my lathe and specifically asked for the bearings that they use and I was quoted $300 for the assembly, so I can only assume that the bearings they use are C-2's and the same as quoted by TPL. In my research regarding the bearings I did stumble across C-3 bearings in stock for $770 USD ($1100 CDN) which is slightly more palatable than $1500 CDN and 6 month lead time provided by Motion Canada. https://3bgsupply.com/bearings/roller-bearing/387a-3-timken
Lastly, I want to thank all of you who offered up advice, observations and encouragement. I was very concerned that I made a poor purchase and was going to be stuck with a lemon who's cost to repair would far outweigh it's actual value but with your help I have a clear path forward to grind / polish this "turd" into something I can be proud of.
Hi Chad,
Glad to hear that you were able to identify/verify your spindle runout measurements with the help of Dabbler.
I owe you an apology for suggesting that your lathe needs #3 precision bearings; evidently that seems to be one of the changes / upgrades from a 11” series 2000 Utilathe, like yours, to a 1120.
Did you adjust the endplay of your spindle?
Have you had a chance to turn a part using your Shars chuck to see if you still get a high spot?
One thing that still puzzles me a bit: how come the spindle bore has almost 0 TIR and the other reference surfaces have 2 to 5 thou? Its almost as if there was a problem during the grinding of the spindle nose from factory.
My reason for this observation: if the spindle is indeed bent ahead of the main bearing, the bore should also show a significant TIR - like 1 to 1.5 thou - because the wall surface you are measuring is a good 3/4” out from the spindle center line. So the further from center you go, the more the runout (as confirmed by measurement on the nose and flange face).
Just thinking out loud... maybe I am missing something.
Glad to hear that you were able to identify/verify your spindle runout measurements with the help of Dabbler.
I owe you an apology for suggesting that your lathe needs #3 precision bearings; evidently that seems to be one of the changes / upgrades from a 11” series 2000 Utilathe, like yours, to a 1120.
Did you adjust the endplay of your spindle?
Have you had a chance to turn a part using your Shars chuck to see if you still get a high spot?
One thing that still puzzles me a bit: how come the spindle bore has almost 0 TIR and the other reference surfaces have 2 to 5 thou? Its almost as if there was a problem during the grinding of the spindle nose from factory.
My reason for this observation: if the spindle is indeed bent ahead of the main bearing, the bore should also show a significant TIR - like 1 to 1.5 thou - because the wall surface you are measuring is a good 3/4” out from the spindle center line. So the further from center you go, the more the runout (as confirmed by measurement on the nose and flange face).
Just thinking out loud... maybe I am missing something.
Was just typing when Rudy posted. That's what I was wondering too.
Maybe my understanding of D-spindles is flawed. I thought that tooling had to fit simultaneously to the taper cone (red) and the back face (green). The orange has clearance to the adapter plate so doesn't really factor. So if you grind either 'fit' faces, I'm not sure how it can mate the adapter/chuck properly. ie. if its eccentric right now (as opposed to cleaning up a raised burr superimposed on a otherwise good circle) then by the time you have ground the cone smaller, it would now have resultant radial clearance relative to the female plate 'socket' side, no?
I had an issue on a wonky face plate where the taper angle was correct but it was shallow to the extent it wasn't mating the back face. That caused the plate to be sucked in at varying angles when the camlock pins were tightened. Hence my understanding that the back face being simultaneously flush was critical too.
Maybe my understanding of D-spindles is flawed. I thought that tooling had to fit simultaneously to the taper cone (red) and the back face (green). The orange has clearance to the adapter plate so doesn't really factor. So if you grind either 'fit' faces, I'm not sure how it can mate the adapter/chuck properly. ie. if its eccentric right now (as opposed to cleaning up a raised burr superimposed on a otherwise good circle) then by the time you have ground the cone smaller, it would now have resultant radial clearance relative to the female plate 'socket' side, no?
I had an issue on a wonky face plate where the taper angle was correct but it was shallow to the extent it wasn't mating the back face. That caused the plate to be sucked in at varying angles when the camlock pins were tightened. Hence my understanding that the back face being simultaneously flush was critical too.
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No apology required. You taught me something about bearing tolerances that I didn't know, so thank you. Hopefully the link I posted for the slightly less expensive bearings proves useful.
I am curious too about the vast differences in wear between the bore of the spindle and the spindle nose/chuck mount. Dabbler offered a few possibilities to explain the anomaly. Perhaps the chuck mount is press fit onto the shaft and was mounted crooked. Or the mount is cast iron and relaxed in an unusual way.
My thought is that it may have occurred when a student slammed a loose chuck into the carriage and distorted the spindle nose. Any thoughts on this?
I haven't turned anything in the new chuck yet. Since it is a 4 jaw chuck will it yield any useful information because I should be able to adjust out most of the error, is this correct?
Tom Kitta
Ultra Member
As someone whom made now two back plates for D1-3 the proper fit is on the red surface and touch the green surface. They yellow surface is not touched as the back-plate / chuck usually has lots of air space for swarf or dirt.
The trick is in 1 setting angle correctly and 2 in making the size of the taper very precise. My primitive method is to bore to within about two or three thou and then finish the rest with sand paper & constant re-check against spindle.
Given that setup I have no clue as to how anyone wants to grind red surface on the spindle - size here is very precise. Any change and chuck on it will be loose. Unless you also grind precisely green surface and calculate precisely how much you need. I.e. you need to grind green first and then extend red taper. If lots is removed you may need to shorten yellow.
The trick is in 1 setting angle correctly and 2 in making the size of the taper very precise. My primitive method is to bore to within about two or three thou and then finish the rest with sand paper & constant re-check against spindle.
Given that setup I have no clue as to how anyone wants to grind red surface on the spindle - size here is very precise. Any change and chuck on it will be loose. Unless you also grind precisely green surface and calculate precisely how much you need. I.e. you need to grind green first and then extend red taper. If lots is removed you may need to shorten yellow.
The spindle nose must be dealt with first before introducing the chuck / back plate marriage into the equation. Sounds like you guys have made some good headway but a few more points to ponder. If the chuck taper is egged or abused or otherwise not fitting, that creates a new secondary issue. Hopefully sketch shows what I was referring to. The cones are not mating axially for whatever reason so even a perfect spindle cannot make a part held in chuck run correctly. The simplest check is to borrow a known 'good' matching backplate fixture or chuck & check that way. Even so you would be measuring relative to a gripped dowel pin or similar so jaw/collet grip enters the picture. But it might help you diagnose if you have a spindle issue or chuck issue or both. For example of someone gripped a pin with his chuck & says it dials in within 0.001" no matter how I bolt it on my D1 spindle and you bolt that same undisturbed chuck/dowel in your spindle and get the same, then we are hinting the spindle may be ok & your chuck is defective. But if your numbers are vary significantly then the spindle is the focus point. Its not scientific but it might be easiest at this stage.
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Hi Peter,
My takeaway from last night and subsequent tests is that the mount has a high spot of 0.005" that is repeatable in the same location. I see your point about the taper not fitting correctly if the plate is ground. Dabbler said that grinding the taper on the cone is a tricky bit of business.
So, I wonder if I will have to order a new spindle nose from Standard Modern and press fit it if that's possible? Or will I be stuck having to shim my chuck to take the slop out? Or remove the spindle completely and send it out to a shop to have it professionally ground?
Are you suggesting that the spindle nose taper needs to be ground first or should I buy a new 3 jaw chuck before getting too carried away?
Your question is slightly higher than my pay grade (hence me wondering out loud if I understand spindles in general). There are more qualified guys on the forum. But reducing an egged spindle cone by grinding sounds like one of those 'I cut it 3 times and its still to short' syndrome.
The starting point for rotating tool interchangeability is spindle nose dimensions & tolerances have to be within spec. You could (maybe) bastardize a chuck to fit but now what - every time you want to change to a different chuck you have no reliable reference because now the 'standard' female socket on back plate will always be slightly larger than the re-ground spindle cone. The camlocks just provide axial pull, not axial or radial alignment.
The starting point for rotating tool interchangeability is spindle nose dimensions & tolerances have to be within spec. You could (maybe) bastardize a chuck to fit but now what - every time you want to change to a different chuck you have no reliable reference because now the 'standard' female socket on back plate will always be slightly larger than the re-ground spindle cone. The camlocks just provide axial pull, not axial or radial alignment.
Yup, and I'm suggesting there could be more to the story. Defect on the left is a somewhat isolated raised bump but the other 99% of section remains circular. For example when you hit a surface with a chisel, there is a resultant negative indentation but typically also a positive raised surface on either side just based on material flow. For example resultant from a deep scratch or better yet an embedded chip. Anyways this type of defect could be stoned off & you are back in business because you are back to mating on the good 99%. So if the DTI needle jumped within a few rotation degrees it would indicate this type of distortion.
But if its more like right sketch where the circle is actually eccentric, that's a different issue. DTI test should show a gradual climb to the max runout. Grinding this shape to the mean minimum circle will result in a smaller circle. Now, was it this way to begin with & you actually have some excess meat to grind to a dimensional spec spindle?. Rudy is one step ahead by providing the spec dimensions. But OTOH if it was circular & good to begin with and now its distorted, that's a more difficult problem because the re-grind would have to be smaller than spec.
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I would describe the bump on the spindle taper to be like the first diagram, a rather pronounced change, but the face of the chuck mounting surface to be like the second diagram.
Is there any visible difference in the spindle where the DTI change is, like axial scratches or gouge? Or does it look smooth everywhere & the DTI just reads this bump?
Another advantage of mating a known 'good' taper fixture is you can blue the spindle with felt pen, gingerly mate the good fixture & see what kind of shiny pattern you get. This gets a bit tricky because it could be rubbing on both sides of the raised dimension. But a shallow stripe or more isolated interference rub off would be good news over a broader area.
Another advantage of mating a known 'good' taper fixture is you can blue the spindle with felt pen, gingerly mate the good fixture & see what kind of shiny pattern you get. This gets a bit tricky because it could be rubbing on both sides of the raised dimension. But a shallow stripe or more isolated interference rub off would be good news over a broader area.
The taper and face of the spindle feel smooth to the touch, no significant scratches, dents or dings.