Dumore 44 tool post grinder mounting on Logan 400

I am pretty new to machining. I purchased a Dumore 44 tool post grinder and I want to mount it to a Logan Lathe.

The grinder works fine except I still need to purchase a number 2 pulley for it. I'll probably have to purchase some wheels for it too. I have one that seems to be in good shape for now.

The grinder is about .135" tall of the spindle center line. Is that a big deal to be that far above the spindle center line?

I can chuck up the tool post stand and remove some of the base to make up some of the difference. I might be able to remove .135" from the base of the grinder base, but this would leave me with about .075" for the flange thickness.

I want to get the tool post grinder set up correctly (or close to it) before I start to grind stuff.

Looking forward to some advice. What would you do?

Dave

Your base is "domed". Mine is flat, and causes no trouble at all. Seems like you could flatten yours, and get what you need.

Mine is also on-center for a 10" Model 200 without being all the way down on the base. A model 400 is a 9", presumably accounting for the issue.

Hi JST,

Yes, the Logan 400 is a 9" lathe. I'll determine if I can get the grinder spindle to be at the same height as the lathe spindle by machining down the dome. I was considering to removing the base material from the flat and leave the dome material, but it might make better sense to remove the dome (or, it might not make any difference).

About how close does the grinder spindle center line height have to be to the lathe centerline height Is like .010" off OK or do you need to be pretty much spot on?

Dave

My Dumore 57 is also too high for my small Logan. I need to rig up a big right angle bracket to mount it, because there's no other way. It's a huge issue if you ever want to grind a taper, which is the main reason I'd ever grind on the lathe. You really need to be on the correct center height.

That's good to know Conrad. I'll work on getting the tool post grinder spindle at the same height as the lathe spindle. Modifying the grinder post wont be that difficult, but making a repeatable method to measure the spindle heights will be challenging. I am thinking of using a 3/8" drill rod in my chuck (which will will have the TIR as close to zero as possible) and comparing the heights of the tool post shaft (which is 3/8") with the drill rod. If I can make the dial indicator be the same for both the drill rod and the tool post grinder spindle, they should have the same center. I'm not sure how else to measure it, given the way things are made.

Yes, I'm going to be using my Tool post grinder for making a MT2 taper and for finishing case hardened punches and dies.

Dave

Isnt that domed base just a spacing washer? Make a new spacer that is the correct spacing. The domed one if it had its mate would allow some adjustment by rocking it, like a lantern tool post.

Howdy,

The dome is not a washer, but it is just a feature on the single piece spacer between the tool post main body and my compound. It has a flat on it for the tool post grinder to sit.

I machined the spacer/post for the grinder. It was somewhat of a challenge to develop a method to measure the tool post spindle relative to the lathe spindle. I think I figured out a method to do it. Anyways, I believe that my tool post spindle is now within .0005" of the lathe spindle height. I'm pretty happy how it turned out.

I also rewired the tool post grinder, added a proper ground, etc. The bearings are gradually getting broken in and are running really smooth and are significantly cooler than the first time I fired up the grinder a month ago. The grinder is pretty old (made before they put belt guards on them) but I don't think it was used much. The grinder has the shelf wear which one would expect from something this old.

My first project with the grinder will be to clean up the tips on my dead centers for my lathe. Then, I'll get back to making my case hardened punch and die sets for my press. I'd like to use the tool post grinder to insure that I hit dimension and that the punch side walls are very smooth.

I'll have to look for some wheels. It looks like Dumore has the best selection but MSC is quite a bit less expensive. I read where one should use something like a 80 grit wheel, but I'm not sure the resin. I'll be grinding low carbon steel and case hardened steel. I think the hardness for my case hardened punches is around 60 Rc.

Dave