Anyone know the bed bolt torque specifications for a 10EE?

[Hobby Racer]

I'm re-mating the bed to the base of my 42 round dial 10EE and would like to know if there is a torque specification for the 6 bolts that secure it.

 

[m-lud]

I'm re-mating the bed to the base of my 42 round dial 10EE and would like to know if there is a torque specification for the 6 bolts that secure it.

When I run into this something that doesn't give torque specs I go to a general torque chart by bolt size and the grade of the bolt. On the headstock I would use the torque specs for a tractor transmission to the engine with consideration of bolt size and grade.
I cant recall ever seeing torque specs in an a machine manual. After you twist enough bolts in life you get a feel for it. I still get the torque wrench out for engine assembly but not much else. The headstock is important to get right.


Here is a useful chart.

Bolt Grades Torque Specs cahart (industrialmetalsupply.com)

 

[Mr_CNC_guy]

This type of thing is special, you are not in a high stress situation. You want to hold
the bed in place while minimizing any stress applied to the casting. You want to draw
the bolts up tight but not really torque them.

 

[Hobby Racer]

This type of thing is special, you are not in a high stress situation. You want to hold
the bed in place while minimizing any stress applied to the casting. You want to draw
the bolts up tight but not really torque them.

That what I figured, thanks.

 

[texasgeartrain]

On a 10ee you would in general level the machine as a whole by using the the 3 casters under the base. However, for correcting any bed twist, this would have to be done by the contact area between base and bed.

If it were me in this position, I'd precision level the base with bed removed. Using the bed mounting area as my leveling reference/surface.

Then install the bed with the bolts pulled tight. I don't personally need a torque wrench for this. But if you have a 5/8" bolt and only pull it to 40 lbs, well its too loose. Bolt sizes are not really random. If the manufacture used a certain bolt size, it was done with the thought it will be tightened to roughly its standard torque.

Anywho, with base precision leveled, then bed mounted. . .now precision level the bed. If its "in", great. If not, I'd shim the bed to whatever direction needed, and pull bolts tight again. Rinse and repeat until the bed is leveled with bolts pulled tight.

 

[rke[pler]

On a 10ee you would in general level the machine as a whole by using the the 3 casters under the base. However, for correcting any bed twist, this would have to be done by the contact area between base and bed.

If it were me in this position, I'd precision level the base with bed removed. Using the bed mounting area as my leveling reference/surface.

I think this would be the wrong way to go. As I understand the process the base and bed were mated by scraping one or the other without regard to the levelness of either base or bed, then after being mated with as little stress between the 2 the whole assembly was leveled using the bed as the reference knowing the bed was under as little stress as possible. Shimming between the base and bed will add exactly that stress.

 

[Hobby Racer]

... Shimming between the base and bed will add exactly that stress.

I simply reused the factory shims in the correct locations. The factory shims ranged from 0.001" to 0.006".

You can see the shims here when I separated the bed from the base.

 

[texasgeartrain]

I'd prefer to not have to do anything . But cast iron, particularly old iron, changes over time with growth, warpage, etc. Shims already in there is telling me something.

If you happen to own a .0005" level, it costs you about 10 minutes of your time to do a check and see, even if you opt to change nothing. But as a simple experiment, you can learn something with the base level, then watching level on bed as you tighten it down. Best part is you won't need to guess and wonder, you'll see the numbers first hand.

 

[rke[pler]

I'd prefer to not have to do anything . But cast iron, particularly old iron, changes over time with growth, warpage, etc. Shims already in there is telling me something.

If you happen to own a .0005" level, it costs you about 10 minutes of your time to do a check and see, even if you opt to change nothing. But as a simple experiment, you can learn something with the base level, then watching level on bed as you tighten it down. Best part is you won't need to guess and wonder, you'll see the numbers first hand.

I believe that some of the wartime production machines had some expedients to reduce manufacturing time. My '56 had the bed scraped to the base (or maybe the reverse) so that clamping wouldn't stress things.

It's easy enough to check during the reassembly with marking compound. If there's good contact with the feed unclamped it's pretty hard to add any stress by clamping it, cast iron doesn't compress that much.

 

[MCritchley]

The war time machines had shims.

And as others have said, do not twist the bed by tightening the bolts. A level will tell you a lot when you are tightening the bolts.

Don’t forget to oil the fasteners, never install a dry screw in a machine tool.

 

[Colt45]

Shimming works but it's not ideal.
Whether that matters or not is up to you to decide.
Believe best practice is to scrape the bed to base fit for proper contact. The factory spec for the bolt torque of the headstock to base is actually pretty high, could be the similar for the bed to base.

https://www.practicalmachinist.com/...gearbox-removal-100049/index2.html#post324988

 

[Hobby Racer]

Shimming works but it's not ideal.
Whether that matters or not is up to you to decide.
Believe best practice is to scrape the bed to base fit for proper contact and the factory spec for the bolt torque is actually pretty high.

https://www.practicalmachinist.com/...gearbox-removal-100049/index2.html#post324988

I think you guys are getting off track. Its NOT the headstock I am talking about. It's the bolts that secure the bed itself to the base casting.

The shims I found there appear to be factory originals so I'm going with what they used. My headstock IS scraped in to match the bed, no issues there.

 

[rke[pler]

I think you guys are getting off track. Its NOT the headstock I am talking about. It's the bolts that secure the bed itself to the base casting.

The shims I found there appear to be factory originals so I'm going with what they used. My headstock IS scraped in to match the bed, no issues there.

Nope, we're talking about the bed to base interface. In my '56 it was scraped in and I just barely had to touch it up in my rebuild, I recall it was about 2 passes to get close to 50% coverage over the feet on the base. So far as I know the intent there is to keep the bed in the same stress as when it was ground by matching the base to the bed feet before clamping.

Headstock scraping to the bed is not as easy since the points you're scraping are so close together. On the base you can take a bunch off one end and the other barely moves, on the headstock you make a pass on the flat and the V changes indication. Plus on the bed you can do the scraping blind - you're not doing it for alignment, you're just scraping for good contact. Headstock you're playing with 2 axis and tenths at 12". It was not easy.

 

[texasgeartrain]

I believe that some of the wartime production machines had some expedients to reduce manufacturing time. My '56 had the bed scraped to the base (or maybe the reverse) so that clamping wouldn't stress things.

It's easy enough to check during the reassembly with marking compound. If there's good contact with the feed unclamped it's pretty hard to add any stress by clamping it, cast iron doesn't compress that much.

To be fair I have not leveled my 10ee yet, as its waiting in line for a rebuild. But just looking at the 10ee design, with heavy base and bed mounted on top, I think there is no way you're correcting any bed warpage or twist by adjusting the base casters.

And this is not a rip on Monarch, design, or the iron itself. I simply see everything move with stress relief, time, etc. No matter how rigid or nice the build. Look at clamping something on a mill, or even using a mag chuck on a surface grinder. You will move, and distort some, with little effort.

Engine blocks and big gear boxes need to line bored over time as they develop twists. Milling machine tables develop an arch bend over time. . .on and on.

My Monarch 61, with no effort I can twist the bed like its rubber just by easing the adjusters a hair. And thats part of the natural leveling process.

Now we're not talking a 1/2", but I would expect .001" to .005" adjustments to any lathe bed reasonable. And in some accuracy tests, like a two collar test you would slightly adjust the the bed to get dialed into to tenths accuracy. Being the 10ee's claim to fame is accuracy, I'd expect this must be done to achieve those kind of numbers.

And on 50-80 year old machines. . .been moved and bumped into, road on trucks how many times . There must have been some stress relief in both the base and bed. Its easy enough to check and see though.

Something like a headstock, yea, I don't want to wrack or twist that. Lathes can do really nice work without straightening bed. But if you want really high end accuracy numbers, its just a fact of life that the bed will need to be adjusted.

.001" to .005" changes in a bed or base from 1950 are not unexpected, or disastrous. I think no one really needs to go to such lengths. But these days I'm more inclined to run those checks and make adjustments if I'm doing a serious rebuild.

Just my opinion, I could be wrong .

 

[texasgeartrain]

Nope, we're talking about the bed to base interface. In my '56 it was scraped in and I just barely had to touch it up in my rebuild, I recall it was about 2 passes to get close to 50% coverage over the feet on the base. So far as I know the intent there is to keep the bed in the same stress as when it was ground by matching the base to the bed feet before clamping.

If I have a .002" twist to the bed with it unbolted and sitting free. . . Then either scrape or shim the bed to mate and contact with base perfectly. . .I would presume I have now incorporated that twist into the final product, and it will still have a .002" twist.

The only way I can see to remove that twist, is to scrape or shim accordingly to pull it straight when tightened down. Could be I'm missing something. But I just can't see neither base or bed holding to inside of .001" from the day it was manufactured till now.

 

[rke[pler]

If I have a .002" twist to the bed with it unbolted and sitting free. . . Then either scrape or shim the bed to mate and contact with base perfectly. . .I would presume I have now incorporated that twist into the final product, and it will still have a .002" twist.

The only way I can see to remove that twist, is to scrape or shim accordingly to pull it straight when tightened down. Could be I'm missing something. But I just can't see neither base or bed holding to inside of .001" from the day it was manufactured till now.

The problem with that is that if you correct the twist in the bed with torque mounting it to the base you're just putting stress in the base that the base will eventually respond to by warping itself. I'm not saying that the bed can't warp but I suspect that it's going to be hard to distinguish warping from wear except that warping would keep the feed from all having solid contact with the base.

In my case my bed was in the same state as when it was put together by Monarch - freshly ground for the whole length after being placed on the grinder feet down and clean. So scraping the base to match the bed feet was the way to go. Your mileage may differ.

 

[AlfaGTA]

Think the difference here is that the discussion is about remounting a bed that is freshly reground....
Now assuming that the way grinder knew what he was doing and did a good job, there should not be any twist in the bed when it was in the relaxed (unmounted ) state....

Given that, i am with rke[pler in that you would want to have good contact (blue) between the base and the bed mounting points with everything relaxed...Old beds not reground, are another
kettle of fish...

Cheers Ross

 

[rimcanyon]

I went through this when I installed a new bed on the 59 (the bed was from a slightly older mfg. lathe). Posted some articles about using an autocollimator to check the bed for straightness as it was fitted to the base casting. I ended up using one shim (from a war-time round dial machine) on the back tailstock bed casting, but I was also compensating for wear. I think that since your bed is freshly ground, use of a precision level to check for twist and bow would be the way to go. You need to level the base casting as a starting point, but you need to have a systematic approach to get the best results. One thing to keep in mind is that the headstock portion of the bed is slightly independent of the rest of the bed. Look at the bolt pattern, you will see what I mean. e.g. if you shim the bolts at the front of the headstock higher, it will cause the headstock to tilt up and the bed to tilt the opposite direction, so you need to check the level everywhere as you tighten.

 

[220swift]

Hobby racer
Call Monarch and ask to talk to Scott. He can tell you the torque they use and
If the bolt threads are dry or oiled.

Hal