Meuser Lathe Spindle Runout

afuege · Post by **afuege** » Sat Mar 21, 2009 10:50 pm

I recently picked up this Meuser M0 lathe:

I checked the spindle before purchasing it (with the collet closer mounted) and only got about half a thousandth runout. I mounted the chuck once I got it home and found that it was out just over three thou.

I unmounted the chuck and checked at the spindle nose. As can be seen from the photo, the spindle nose is out by just over two thousandths:

I checked the spindle for play and found nothing. Next, I attempted to check the taper fit, but the split ring prevented me from getting a good seat. I decided it was best to pull the spindle out and do the fit on the bench. I opened the gearbox and removed the bearings:

I was surprised by the condition of the bearings. This lathe was built in 1957, and the bearings still look pretty good:

Next I pulled the spindle out. I got it on the bench, removed the key from the taper, and hand fitted the backing plate to the spindle. Here's the result of the test fit:

I obviously have a problem with the spindle taper. I got the same results when I fitted the spindle to the chuck and the collet closer.

Now I have to figure out how to fix it. More to come on that.

-Arthur Fuege
Somerset, New Jersey[/img]

mystry_tour · Post by **mystry_tour** » Sun Mar 22, 2009 10:30 pm

What is the taper. Can you lap it to the spindle
Reg

crzypete · Post by **crzypete** » Mon Mar 23, 2009 10:07 pm

Arthur, Rotten luck on the spindle. Definitely a moment not to half ass it, have it reground professionally. It will be worth the $$ in the long run.

Reg, The spindle is an L series and looks to be an L-1.

Arthur, any clue how it got damaged? Those L spindles are practically indestructible. I am definitely surprised.

Pete

afuege · Post by **afuege** » Tue Mar 24, 2009 6:24 pm

The spindle is an L0. I'm not sure how it got messed up. It looked good, no dings or even scratches. My guess is that someone tried to regrind it and didn't get the taper right. I took it to a friend of mine (who is actually a machinist). He chucked it up in his lathe and we trued it up using a toolpost grinder. It took a few passes, but we were able to get it reading dead on, then we verified the fit using prussian blue. I managed to get the spindle back into the machine late Sunday. On my initial run with the faceplate mounted, it was running out about a half a thousandth. Obviously much better than where I started. I'm travelling to Minneapolis this week, but will get back to work on this on Saturday. Hope it looks as good with the chuck mounted.

-Arthur Fuege
Somerset, New Jersey

afuege · Post by **afuege** » Sat Mar 28, 2009 7:37 pm

I got the chuck mounted up today and was disappointed to find out that I was running out just over 2 thousandths. I took the chuck off the back plate and checked the backplate by it'self. The plate was running out just over a thousandth. I mounted up the toolpost grinder (Thanks Tim) and ground the mating surface. When I checked it again, I was back to being out about half a thousandth (same as the spindle nose. I cleaned the back of the chuck and re-mounted it on the backing plate. This time it read out one and a half thousandths. I mounted up the toolpost grinder again and ground the jaws.

Here's my final reading after grinding the jaws. This is pretty good since this lathe left the factory in 1957 with one thosandth runout at the spindle nose.

Now I can get back to work on that Oliver cutterhead

Toolslinger · Post by **Toolslinger** » Sun Mar 29, 2009 10:03 am

Glad the Themac worked out!

crzypete · Post by **crzypete** » Sun Mar 29, 2009 8:42 pm

Hey Arthur,

Probably redundant to you, but I thought I'd post in for general knowledge.

I am not sure what your Oliver cutterhead project is, but my guess is that you would be better off with either a four jaw chuck or turning between centers with a dog and drive plate.

Three jaw chucks are just not accurate. they are very convenient to start with a round piece and turn it from there, but you can't rely on them to reclamp something in a consistent way.

I made an indicator holder for my Aloris toolpost. I use this in conjunction with my four jaw chuck and it makes centering to tolerance a snap.

Turning between centers is old school, but is great for shafts that you want to swap end for end and things with threads that you want to be able to pop off the lathe and check how the threads fit.

Pete

crzypete · Post by **crzypete** » Sun Mar 29, 2009 10:35 pm

I found an old crappy pic of my Aloris block with indicator.

afuege · Post by **afuege** » Mon Mar 30, 2009 7:41 am

Pete,
My plan is to make all the heavy cuts using the three jaw chuck. Once I'm withing 1/8" of finished tolerances, I'll switch to the collet chuck. I rarely remove a workpiece from the lathe in the middle of the job. When I do, I'm very careful to reference the work to the chuck. I have a four jaw chuck for this lathe, but I haven't checked it out yet.

The machinist that helped me with the spindle nose had a nice setup for centering. He had a 1" thick steel plate that he machined to fit on his bedways. The spindle was too long to fit between centers, so he had to use a steady rest. He was able to center the workpiece easily with a magnetic based dial indicator, sliding the plate all the way along the bed.

I will have to turn the workpiece once, but that's only for a parting operation. There is a 1.5" threaded area on the end of the shaft, but I plan to use a die to cut the threads.

Your setup with the dial indicator right on the toolpost has got me thinking. It could definitely be useful for a number of operations.

crzypete · Post by **crzypete** » Mon Mar 30, 2009 9:07 am

Ok, now I have to ask..... What is the project? Replacing a clamshell? How big a jointer?

Also, when cutting threads with a Die, my preferred method is to just use the die to finish what I had started single-pointing on the lathe. This method guarantees alignment and is much less taxing on the die.

Also, you may want to be aware that the accuracy of the three jaw may change at different diameters- This is due to the scroll wearing.

The plate sounds interesting, However I am not sure I grasp how it avoids the carriage?

Pete

afuege · Post by **afuege** » Mon Mar 30, 2009 10:16 am

Pete,
It's a 16" direct drive jointer. I'm replacing the 4 knife Clam-shell with a 4 knife head.

The thread on the end of the shaft is 1-1/2-18. It's also only 5/8" of threaded area. I haven't tried cutting anything that short or fine on this lathe.

I've learned the hard way about the accuracy of self-centering chucks. Now I check every time.

You're correct on the plate. It works well for operations where the carriage is behind the steady. Otherwise, you're better off referencing from the carriage.

crzypete · Post by **crzypete** » Mon Mar 30, 2009 9:11 pm

Arthur,

Don't be put off by the fineness of the thread. It is actually easier to cut than a coarse thread. You do not have to go as deep and more importantly the carriage moves less in relation to the revolutions of the spindle.

When possible I like to cut to a parted groove- this makes pulling the bit back very easy.

Also, in situations like this, triple check that it is not a left handed thread.

I hope you will take us through the project as you progress, cutterheads are definitely projects that many of us have thought about making.

Pete

afuege · Post by **afuege** » Tue Mar 31, 2009 7:12 am

Pete,
I'm sorry/happy to say that the project on the cutterhead is just winding down (after a 6 week delay ironing out the issues with the lathe). I purchased some NOS Delta heads from a machinery dealer. The one I'm working on now was a 24" 4 knife head from a planer. The diameter matched the original Oliver head exactly. This is a direct drive 16" jointer, so the head needed to be turned for for the motor shaft. One end of the Delta head was already drilled and tapped. It also had a keyway cut into it. I took advantage of that and used that end for the motor shaft. I've already turned that side of the head down and I'm now working on the front bearing. I'm pretty sure I'll get through that this Saturday and will be on to threading the end of the shaft. The final step will be to grind all the mating surfaces to finish tolerances. I'm hoping that this will be complete this weekend.
I'm also starting to think about balancing. I've got a set of balancing stands, just not sure that will be sufficient for a part this small in diameter. I've done a few cutterheads in the past and never had a problem. However, I have read about others that encountered issues using a reworked head.

afuege · Post by **afuege** » Sun Apr 12, 2009 6:57 pm

I finally got some time in the shop this weekend and have the cutterhead project moving along nicely. I managed to get the end of the shaft threaded. This turned out to be a non-event. I had been worried about the small area to be threaded. Other than it being very close to the chuck, it was pretty straightforward. I ended up starting from the bearing side of the thread and cut towards the end of the shaft. This worked out nice since there's a groove cut between the bearing shoulder and threaded area. I used carbide insert thread cutters. They're pre-cut for the pitch/angle. The nut went on and fit perfectly on the first try.

I also had to cut the keyway for the motor. I did this on the Cincinnati mill. Once again, no surprises. Here's the current state of the head:

I'll start looking for bearings this week, and then on to reassembly.