# What Model Dumore Tool Post Grinder For A Sb9a?



## thenrie (Nov 19, 2015)

Anybody have an opinion on which model Dumore tool post grinder would be appropriate for a South Bend 9A lathe? I have been thinking about buying one, but I don't want to spend the money and find I've over-sized it. I just want to be able to polish shafts, inside bores, some homemade morse tapers and centers, etc. 

Right now I'm looking at a Model 5 and an 11-01 on eBay, but don't know much about them. Can't seem to find much info on them that shows their relative sizes. Can't tell much from the photos.


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## Bob Korves (Nov 19, 2015)

The most important thing is that your lathe fits in the range of possible tool heights the grinder can accommodate.  Measure from the top of the compound where the tool post mounts to the center of the spindle.  That is the tool height.  The grinder spindle must be mounted exactly the same height as the lathe spindle center.  Dumore has a web site where you can see the range of center heights for their grinders.  Catalog data like "fits 11-15" lathes" is misleading, tool height is what makes it work or not.  Beyond that, what do you plan to do with it?  There are tool post grinders that only do I.D. work, only do O.D. work, or both.  The range of spindle speeds is related to the size of the grinding wheels used, small wheels use higher RPMs and large wheels use lower RPMs.  If nothing else, study the Dumore site, look at the various grinders, and see the ranges of speeds available and what size wheels that allows.  Horsepower becomes important if you are doing heavier stock removal or care about how long the job takes.  Most tool post grinders are pretty light duty machines.
http://www.dumorecorp.com/


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## Bob Korves (Nov 19, 2015)

Another consideration is the horizontal grinder spindle offset from the tool post center.  Crank your cross slide all the way back.  Measure the horizontal distance from the spindle center to the tool post center.  That distance, minus the grinder spindle offset, minus half the grinding wheel diameter, is the maximum cylindrical grinding diameter capacity.  Hint, it will not be anywhere near 9"...


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## thenrie (Nov 19, 2015)

That's the problem with buying online. You don't get to do all those measurement things. You just get the model number and ask questions. The one I'm looking at is a No. 5, which appears to be the forerunner of the current Series 57. It has changeable spindles. The seller says it came off a SB9 and the Dumore info re the Series 57 indicates it will fit a 9" lathe. I expect I can re-sell it if it doesn't fit, but it appears to be what I want. Thanks for the quick input.


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## Mister Ed (Nov 19, 2015)

I have a series 11 for my 10" Logan, fits pretty nice ... I just don't use it much.


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## bob308 (Nov 20, 2015)

I have one I use on my 9" . it fit and works nice. also with spacers it works on my 14 1/2 " southbend. I will get the numbers on it in a day or two I left it at my other shop.

things to remember when using one. I cover the carriage and ways with a leather welding apron also lay a piece of metal where the sparks hit. after you are done clean up the lathe real good. as in wipe it down with paper towels till they are clean then re oil.


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## thenrie (Nov 20, 2015)

Ok. It looks to me like the series 57 and series 11 and 44 are about the same size. The No. 5 has a 1/2hp motor, whereas the 11 and 44 have a 1/4hp, but the size seems to be about the same. Should work.


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## 4GSR (Nov 20, 2015)

thenrie said:


> Ok. It looks to me like the series 57 and series 11 and 44 are about the same size. The No. 5 has a 1/2hp motor, whereas the 11 and 44 have a 1/4hp, but the size seems to be about the same. Should work.



Those are all too big for use on the 9" SBL.  

Need to find the No. 7 Tom Thumb Dumore tool post grinder.  It's the correct size to use. It's what I have and use on my 9" SBL.  The no. 11 and 44 may work, may not.  The no. 5 or series 57 are way too big to use on the 9" lathe.

Ken


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## thenrie (Nov 21, 2015)

Yeah. I missed the one I was bidding on. I guess that's good, in light of the info I'm getting. I'll just keep watching.


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## Mister Ed (Nov 21, 2015)

I tthink the 11 actually had a 1/5 hp motor (not that its that big of difference). Oh in the #11 instructions, it does say from 8" to 11" ... and then goes on to talk about the height from carriage etc, I forgot to mention that the other night.


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## thenrie (Nov 27, 2015)

I ended up getting a Dumore #44. The website indicates it is sized for 8"-14" lathes, has a 1/4hp motor. Comes with several pulleys of various sizes and a wheel or two. I haven't received it yet. Bought it off eBay for $182, including shipping. I'll have to wait until it gets here to decide whether I did well or not, I guess.


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## n.glasson (Dec 14, 2015)

I have just picked up a Dumore No.5 for the right price and plan to fit it to my Harrison L5.  The spindle centre height is about 6mm too high if I just bolt the Dumore down to the compound slide.  After a bit of thinking, my fix is to fabricate a custom mount that will tip the Dumore thru 90 degrees.  Basically an angle plate - similar to the one that mounts the vertical slide.  The Dumore spindle can be about the same horizontal distance from the centreline of the compound slide.  The Dumore will end up with the motor up a bit higher and the belt going up-down rather than towards and away from the operator.  I have some chunky short lengths of angle iron that I can gusset to make a very rigid bracket.  A lump of cast iron the right size would perhaps be better.  You could then choose to machine it at an angle a bit less than 90 degrees if you wanted to optimise the orientation of the Dumore.


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