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10ee Square dial QCGB tumbler lever

Mr_CNC_guy

Cast Iron
Joined
Jul 29, 2018
Location
New England
I am doing a paint job on my 10ee. I removed all of the
handles for convenience. All of the taper pins knocked
out without too much difficulty except for one. That one
I had to drill out.

Now comes reassembly and they all go together OK except for
that one. The taper pin will not go in. Clearly the lever
and the shaft do not align.

Here is a #4 taper pin in the lever and in the shaft.
They both seem to fit OK.
DSC02339.jpg

Here is an attempt to fit them together. The pin only begins
to enter the hole in the shaft. There are no burs. I have
cleaned both things with a tapered reamer.
DSC02341.jpg

The original pin is in small pieces and was clearly too short
to go all the way through. It must have been pounded in.

I can use a taper reamer to make the new pin fit but I worry
that the alignment of the lever and the shaft will be wrong.
If I force the taper in as it is the lever engaging pin
will not close over the notch in the housing. The lever
will not lock in place. That is clearly bad.

It is likely that the lever was swapped between some other
10ee sometimes in the past. Unfortunately I only have this
one 10ee.

How can I get the correct alignment between the lever and
the shaft? Do I have to take apart the gearbox to check
the gear alignment? Is this a critical adjustment?
 
Last edited by a moderator:
Its the tumbler lever for qcgb. Up position with pin locked, it needs to have back lash with whichever gear was selected by spinning large chrome knob.

Down position, when pin is pulled would be disengaged.

Think like an open tumbler type qcgb, those you can look up and see a single gear on tumbler arm.

You don't need alignment, as big chrome knob selects alignment. But you need decent backlash with whichever gear when you lift that lever and let pin fall. I'm thinking there must be a way to adjust for decent backlash, I just don't know how that's done yet.
 
I am doing a paint job on my 10ee. I removed all of the
handles for convenience. All of the taper pins knocked
out without too much difficulty except for one. That one
I had to drill out.

Now comes reassembly and they all go together OK except for
that one. The taper pin will not go in. Clearly the lever
and the shaft do not align.

Here is a #4 taper pin in the lever and in the shaft.
They both seem to fit OK.
View attachment 333813

Here is an attempt to fit them together. The pin only begins
to enter the hole in the shaft. There are no burs. I have
cleaned both things with a tapered reamer.
View attachment 333814

The original pin is in small pieces and was clearly too short
to go all the way through. It must have been pounded in.

I can use a taper reamer to make the new pin fit but I worry
that the alignment of the lever and the shaft will be wrong.
If I force the taper in as it is the lever engaging pin
will not close over the notch in the housing. The lever
will not lock in place. That is clearly bad.

It is likely that the lever was swapped between some other
10ee sometimes in the past. Unfortunately I only have this
one 10ee.

How can I get the correct alignment between the lever and
the shaft? Do I have to take apart the gearbox to check
the gear alignment? Is this a critical adjustment?

You could tap for a set screw in the handle at 45 deg position from the pin position. Use the set screw to set and lock your correct position of the handle . Then ream your pin taper.
You could drill for one pin size larger to really clean the tapered pin hole. Make sure a larger pin isn't making the shaft weak from the larger diameter hole.

Edit
After reading texasgunsmiths post. My suggestion may not help your issue
 
Realizing after the fact there's more than one big chrome knob :D, I meant the one under the square threading chart.

I've not had the 10ee apart, so I don't know what's behind the square threading chart, but I think there's a chance you can see and watch the tumbler as you move that lever up and down, might be able to check back lash as well.

Not a 10ee, but the series 61 is similar. You can see the slots that choose alignment with the knob. Moving the lever up or down, engages or disengages to select another gear:

28.jpg

Anyway with the square chart off, you might have a view. Might have an addition plate to remove after the charts off, for full view. No doubt there's pics or someone who knows here.
 
I was wondering if the lever is tight when locked into place.
The chrome pull handle retracts a wedge shaped pin that engages
the hub on a slanted surface. Does the wedge press against the
slanted hub when locked into position? When the lever is engaged does
it have any slop or is it wedged tight into it's position?
Knowing that would help me knowing how to position the lever
when I come up with a solution.
 
On an open air qcgb, you physically raise and lower the tumbler arm, and slide to what gear position you want. Somewhat simple and direct.

The 10ee style is more complicated, think rube goldberg, but more precise and cleaner as no dirt or chips get to it.

The action of lifting the 10ee lever in essence is lifting the tumbler arm into engaged position, but not directly as there is more pieces involved, but it is lifting the tumbler all the same.

I'd say you don't want locked tight on wedge of chrome handle, as the tumbler gear will have no backlash to which ever gear it is now engaged. After the chrome handle pops into slated hub, keep pushing up on handle will move tumbler gear closer to mating gear and remove back lash. While the opposite happens when you pull chrome handle and move lever down, backlash will increase until you are fully disengaged.

Doing it blind, I'd want to use chrome knob under thread chart. Start at the beginning, disengaged lever plus knob turned fully counter clock wise. And check each engaged position by turning knob clock wise for each next step on thread chart. You will occasionally butt the teeth of gears before getting engaged, probably need to spin leadscrew (or potentially spin the head stock) a little to make all the engagements, with "threading" selected on the other lever.

Anyway, I'd want chome handle to drop into slanted hub nice, with just a little room to go a little more, not tight on slanted hub. I'd want gear backlash. I have not had my 10ee apart to really know, but I have inside of 1/16" I can push more on chrome lever after its engaged on slant cut hub, maybe 1/32" or somewhere in between a 1/16 and 1/32.

Without laying eyeballs and fingers on gears, I would say that 1/32-1/16" extra push takes backlash to zero. So I want that little bit of play.
 
From your second photo, it is clear that the handle and shaft are a few thou out of alignment, maybe .010 to .020”

Maybe they are not mated parts, i.e. the handle might be from a different machine.

I would suggest removing the round part with the detent notch then pull out the shaft and check the taper pin fit on the bench.

Here are some photos from my 59, and as you can see it is a very simple assembly. If you installed a new bronze bushing, it may be too long, so first try fitting the handle to the shaft without the bushing. If that works, measure the gap and cut the bushing to fit.

IMG_1712.jpg

IMG_1711.jpg
 
From your second photo, it is clear that the handle and shaft are a few thou out of alignment, maybe .010 to .020”

Maybe they are not mated parts, i.e. the handle might be from a different machine.

I would suggest removing the round part with the detent notch then pull out the shaft and check the taper pin fit on the bench.

He's determined they are not mated parts. Before running a taper pin reamer through it, he's trying to determine the correct location of handle when it drops into detent, or if there is a way to adjust to correct the location for acceptable backlash on gears.

I'm not sure if there is a way to adjust tumbler height for gear engagemnet with backlash. Do you know how to check or potentially adjust the engaged height of tumbler gear ?
 
You are correct texasgunsmith, I believe that the parts are not mated and
that is the problem that I have to fix.

I took the thread chart plate off to get a better idea of the gearbox
mechanism. The lever slides a plate that locks the gear that you have
selected into place. This plate has a series of notches that sets
the depth of engagement (backlash) and also prevents the gear selector
from moving out of position.

Here is a picture of the mechanism:

DSC02348.jpg

The notched plate can be seen at the very top of the opening. That
plate moves in and out with rotating the lever. Rotating the selector
knob seen at the bottom of the picture slides the block with the pointer
to the left and right. This block engages the notches in the plate
at the top. The depth of the notches sets the depth of the engagement
of the gears and therefore the backlash.

The gears cannot he shoved too far into engagement so that is not a
worry. The engagement of the gears is adjustable by the two set screws
shown in the picture, I am pointing to one of them. These set screws
are the stops for the notched plate.

I have moved the lever back a forth and felt the backlash of the gears.
It does not seem to be critical. So long as the lever is close to
holding the notched plate against the stop screws the backlash feels
good. The 1/16" to 1/32" suggestion from texasgunsmith seems a good
number but having the lever locked tight should also work OK.

So, what to do?

I am thinking of making a bushing out of a taper pin and using it as
a drill guide to redo the tapered hole in the shaft. Unfortunately
the taper pins from McMaster-Carr do not seem to be hardinable. I
don't think that there is enough metal in the shaft to make a new
taper pin hole.

Anyone have any suggestions?
 
I would suggest removing the round part with the detent notch then pull out the shaft and check the taper pin fit on the bench.

Here are some photos from my 59, and as you can see it is a very simple assembly.

Those pictures are great, thanks. I had worried that pulling
the shaft might cause some part to come off and drop in the gearbox.
Been there, done that! I can see from your pictures that is not
a problem. That may be the thing to do as I can mount the parts
in my mill and machine the hole for proper alignment.
 
You are correct texasgunsmith, I believe that the parts are not mated and
that is the problem that I have to fix.

I took the thread chart plate off to get a better idea of the gearbox
mechanism. The lever slides a plate that locks the gear that you have
selected into place. This plate has a series of notches that sets
the depth of engagement (backlash) and also prevents the gear selector
from moving out of position.

Here is a picture of the mechanism:

View attachment 333863

The notched plate can be seen at the very top of the opening. That
plate moves in and out with rotating the lever. Rotating the selector
knob seen at the bottom of the picture slides the block with the pointer
to the left and right. This block engages the notches in the plate
at the top. The depth of the notches sets the depth of the engagement
of the gears and therefore the backlash.

The gears cannot he shoved too far into engagement so that is not a
worry. The engagement of the gears is adjustable by the two set screws
shown in the picture, I am pointing to one of them. These set screws
are the stops for the notched plate.

I have moved the lever back a forth and felt the backlash of the gears.
It does not seem to be critical. So long as the lever is close to
holding the notched plate against the stop screws the backlash feels
good. The 1/16" to 1/32" suggestion from texasgunsmith seems a good
number but having the lever locked tight should also work OK.

So, what to do?

I am thinking of making a bushing out of a taper pin and using it as
a drill guide to redo the tapered hole in the shaft. Unfortunately
the taper pins from McMaster-Carr do not seem to be hardinable. I
don't think that there is enough metal in the shaft to make a new
taper pin hole.

Anyone have any suggestions?

The handle doesn't take a lot of force to do its job. A set screw with a small dimple in the shaft may hold fine. You may be able to tap the existing tapered pin hole in the handle. Run the proper drill bit in for the tap
edit
To do that you may have to plug the hole in the shaft with a piece of tapered pin so the set screw doesn't put you in the same out of position situation by following the old hole.
 
There is plenty of meat to install a new pin. Don’t be tempted to enlarge the old hole…

Take the shaft off to do it on the drill press, don’t try and use a portable drill. Use a setscrew to lock the handle in position. Find the position by using the setscrew and keep adjusting until you have it right. When its done the handle should wedge into position, not be loose.
 
20211106_100021.jpgMy handle has a set screw at 45 deg from the pin. I suspect Monarch did that to find and lock the correct position before drilling for the pin. Like in rimcanyons suggestion says. Otherwise its difficult to hold correct position.to drill that handle.

Handles aren't interchangeable without some re-work As you knew
 
The handle doesn't take a lot of force to do its job.

Is that true? The lever moves the gear into position. When the
gear is passing torque then it will tend to be forced out of engagement.
Gears are forced apart as the torque increases. It is the lever
and the spring loaded knob with the wedged end that locks it into
position.
 
Is that true? The lever moves the gear into position. When the
gear is passing torque then it will tend to be forced out of engagement.
Gears are forced apart as the torque increases. It is the lever
and the spring loaded knob with the wedged end that locks it into
position.

I dont think so but I guess that's possible. My lathe hasn't ran but I worked the handles through their moves to learn their operation. My handle shifted easy without forcing anything.
I removed my handles like you to paint.
While running
I have never seen any transmission that much torque would transfer back to the shifting mechanism. I have not had my gearbox apart. The spring pin is to hold position but it shouldn't have much load either
Some one with knowledge of the gearbox will know more
Let me know if that pin is taking torque from gear forces. That would be poor design by Monarch
 
I'm not sure how much pressure is put on the handle while gears are loaded. I would guess something, But I'm thinking x amount is absorbed by the tumbler itself, as well as the rest of mechanism, sliding plates etc.

Again, not a 10ee, but rabler's 612 qcgb. The tumbler cast was broken prior to his purchase, suggesting outward forces. Though the orientation of tumbler and sliding plates differ, I think in principle it works the same as a 10ee square dial. Real nice pics and info for anyone interested:
Anyone familiar with the QCGB on a 610/612?
 
The old qcgb did rely on the pin for enga8gment. I also don't know how much gears try to separate.
I did go out and look at the shifting mechanism.
In the locked in position I pulled back on the idler gear. There is something in there that locks. No handle on the shaft. The idler doesn't just hinge in and rely on the pin in the handle to take the force of the gears disengaging.

The way I look at the pin. If you have two set screws that is equal to one pin. The shear point is at the shaft OD.. A set screw dimpled into the shaft 3/16" is half the pin in strength. Two set screws your good. I think pins are soft to shear rather than break something.
I know that there are outward force's in transmissions but shifting forks are used where forces are greater.

I agree with rimcanyon a set screw to find position and re-drill a pin

Texasgunsmith
Thanks for the link
I looked but will study the thread more. This gives me a new subject to study
 
The engagement of the gears is adjustable by the two set screws
shown in the picture, I am pointing to one of them. These set screws
are the stops for the notched plate.



View attachment 333863

I was curious about the tumbler mechanism, so I pulled my square threading chart off. Mr_CNC_guy is correct, the set screws in front face of qcgb limit the plate travel, which is used to prevent shoving tumbler in too far, and thus backlash can be set this way.

On Series 61 and 612 the tumbler lever has a tit sticking out, pointing towards front side of lathe. The plate catches that tit, and that is what is used to physically lift tumbler to engage/disengage:

151.jpg

Wondering about the 10ee, I moved tumbler into view. We can see the gear, but it appears tumbler body is pointed upward:

152.jpg

Peaking up and around the corner, I can the 10ee also uses a tit at the end of tumbler body. That tit is pointed upward, and what fits into slotted plate above:

153.jpg

And as a side, re-checking my 61, I don't see any plate limiting set screws. But funny enough, I don't need a limiter, I need to go a hair more. My plate travel is a hair from contacting its end run with tumbler engaged. I have slightly excessive backlash. Looking at it, I think I can move the outer lever just a hair more with a sleeve on locking pin. Just moving the lever that small amount makes backlash nice.

Thanks for title edit Cal.
 
I was curious about the tumbler mechanism, so I pulled my square threading chart off. Mr_CNC_guy is correct, the set screws in front face of qcgb limit the plate travel, which is used to prevent shoving tumbler in too far, and thus backlash can be set this way.

On Series 61 and 612 the tumbler lever has a tit sticking out, pointing towards front side of lathe. The plate catches that tit, and that is what is used to physically lift tumbler to engage/disengage:

View attachment 333919

Wondering about the 10ee, I moved tumbler into view. We can see the gear, but it appears tumbler body is pointed upward:

View attachment 333920

Peaking up and around the corner, I can the 10ee also uses a tit at the end of tumbler body. That tit is pointed upward, and what fits into slotted plate above:

View attachment 333921

And as a side, re-checking my 61, I don't see any plate limiting set screws. But funny enough, I don't need a limiter, I need to go a hair more. My plate travel is a hair from contacting its end run with tumbler engaged. I have slightly excessive backlash. Looking at it, I think I can move the outer lever just a hair more with a sleeve on locking pin. Just moving the lever that small amount makes backlash nice.

Thanks for title edit Cal.

That's a nice looking set of gears in there. They are a lot smaller in size than would you think needed but are just driving the feed screw. Although it works pretty hard driving the apron and feeds.
I have the handle off and faceplate off and worked mine back and forth some and was impressed with its shifting mechanics.
I did some reading on how gears transfer power with the Pressure Angle of a gear tooth. Misplaced the link.:rolleyes5:
Texasgunsmith
Be careful. Fooling with the 10ee could get you sidetracked off the 61 series. It's hard for me not to do that. That's part of why my 10ee isn't running yet.
Thanks for digging in there and explaining the mechanics

Mr_CNC_guy
That creates a bit of a mess sometimes with such a small shaft and drilling again. Let us know how it works out.
 








 
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