Another bound-up train…

[david pierce]

Tom,
Those pictures are fantastic and it looks like they show what needs to be seen. An optical comparator will blow the image up on a 14 inch screen but the pictures you have should be all you need. What I would do at this point is get a properly working movement (another watch) and take the same pictures in the same operating sequence. Then compare the pictures to each other. The advantage offered with an optical comparator is the movement can be blown up to an overlay that is laid over the screen. Because of the error reduction offered from the magnafication (as much as 100x) the distances and angles can be precisely determined. I think, however, that you will be able to tell what the problem is with the equipment you have. On the surface it looks like the pallet jewel is sticking out too far but this will be revealed when you examine a properly working movement. You can also compare the stone angles, drop distance etc.
Also, as George Daniels pointed out in his book formulas are at best a ball park starting point. The manufacturing sector then needs to figure out how to make it work. I know from 22+ years designing automated equipment for the electric motor industry there was never one instance I know of where a motor went from design and then directly into production. Watches are extremely touchy and complicated devices and I would bet money that any watch movement that works was modified from the initial design in the manufacturing sector.
david

[tmac1956]

@Bob Tascione wrote:

Tom,
Great close up shots!
In the last pic where no locking occurs, is the banking pin adjusted all the way out to allow full travel of the lever?
Bob

Bob.

I did move pins out but not all the way. I’ll give that a shot.

Thanks,
Tom

[tmac1956]

david:

That’s a good idea. I do have a nice Elgin that runs great. I can un-case it and take a look.

Thanks,
Tom

[Bob Tascione]

Yes Tom that would be a good thing to check before going any further. From your pics it’s easy to see that the locking depth on the one pallet is probably more than twice what it should be and the other is much too shallow. The banking pin could be preventing the lever from moving over far enough to allow locking. If this isn’t the case then will most likely need to adjust stone depth but this should be the last resort. All of these adjustments can be made using a 10x loupe for the size watch you have here.

Bob

[arutha]

Thanks for pointing that out Bob, I keep forgetting about the banking pins!
Paul.

[tmac1956]

Bob:

I adjusted the banking pins all the way out, but it didn’t seem to help. I guess its time I learned how to set pallet fork stones back in at different depths. I have a pallet warmer and shellac so I don’t think that part of it will be very hard to do as I’ve got some good books on this. My problem will be shortening the pallet stone. These are hard up against the fork, so I can’t position them back any further. I guess I ‘ll need to get a diamond wheel for that. Additionally, I’ll need some way to securely hold the stones while grinding them down.

Any ideas? This will be the first time I’ve done this operation.

Thanks everyone!
Tom

[david pierce]

Tom,
Have you definately nailed down the problem? Before wacking away on the pivot jewels make sure you have ruled out everything else. If possible post a set of similar pictures from the working movement so Bob can have a good look at it. A diamond wheel or even a diamond lap will cut the stones down. If you decide to cut them down take the material off of the back of the stones so you don’t disturb the angles.
david

[tmac1956]

David:

Here’s what I did to try and deduce the actual problem. I fully assembled the cleaned and lubricated movement, removed the balance assembly, and wound the watch. The movement didn’t move unless I jiggled the gears – then it would run for a millisecond or so and stop. Next I let down the mainspring, removed the pallet fork, wound it up again, and it ran down non-stop until the power was exhausted.

It just seems to me that it has to be in the pallet fork. Clearly, the balance assembly isn’t tested either.

Any thoughts about what I might have missed? I know I make a lot of mistakes.

Thanks!
Tom

[Bob Tascione]

Hey Tom I’m definitely missing something here .
When you remove the balance the train should remain locked in place as long as the pallet is in place. If the train is spinning with the pallets in place then there would be a problem with the pallet. Are you saying that the pallet shouldn’t allow the train to escape when you jiggle the gears or that the train should turn with the pallet in place?
It sounds like only one pallet jewel is engaging an escape wheel tooth and when you jiggle the train you are kicking the lever over to the side where the pallet stone is too shallow to engage and stop the escape wheel…permitting a few teeth to slip by until the lever is kicked back to its original position and once again locks a tooth.

Bob

[tmac1956]

Bob:

I did assemble the watch with the balance in place. The balance wheel seemed to behave well except that I had to spin the balance to get the watch to run. It would run a little and then stop – not what one would want to see.

I must confess that I thought the train should run even with the pallet fork in place. Lesson learned. Boy do I feel stupid 😳

Ok… Should I start by pushing out short stone? One other question. Does shellac have a shelf life? I have two bottles of the stuff but it looks to be at least 75 years old.

Thanks!
Tom

[Bob Tascione]

Hey Tom don’t feel bad at all Easy to make that mistake.
We have to give William credit for figuring out the problem. I was in a Skype meeting with William, Paul and Jim earlier today and your thread came up in conversation. William and Paul discussed the possibility that you may be a little confused on the pallet action.
Looks like we’re making progress!
Before moving the jewels would it be possible to put a pic up here of the pallet fork in place? Something that shows the lever, banking pins and a few teeth of the escape wheel? As David said in his post, this would be very helpful at this point. In fact a few pics with the lever moved from one banking pin to the other with the jewels intercepting a scape tooth would be perfect. This will be of help when it comes to making the stone adjustment…if needed.
The shellac may be fine. You can test it by heating a small piece while pulling it into a fine thread.. If it pulls fine then it’s probably good.

Bob

[tmac1956]

Bob:

Sure. I’ll get them up as soon as possible.

I appreciate everyone’s help.

Thanks!
Tom

[chris mabbott]

Tom I can’t tell from the pic but isn’t there any space behind the pallet stone to possibly slide it back the amount you need?

The reason I ask is that…. We may see a post saying that the stone went for a fly while trying to grind it 😆 these little turds ain’t easy to remove material from and they chip and fracture easily unless you have a proper wet stone for grinding mineral,that also has some sort of holding device.

[tmac1956]

Chris:

Unfortunately, the stones are hard up against the pallet fork slots. Which means, if I have to grind them, then I’ll need to figure out some way to hold them. Steffen Pahlow built a good holder for this purpose in this video:

http://www.youtube.com/watch?v=fOgmvbOtjYk

Perhaps I can fashion something like that.

Thanks!
Tom

[tmac1956]

@Bob Tascione wrote:

Hey Tom don’t feel bad at all Easy to make that mistake.
We have to give William credit for figuring out the problem. I was in a Skype meeting with William, Paul and Jim earlier today and your thread came up in conversation. William and Paul discussed the possibility that you may be a little confused on the pallet action.
Looks like we’re making progress!
Before moving the jewels would it be possible to put a pic up here of the pallet fork in place? Something that shows the lever, banking pins and a few teeth of the escape wheel? As David said in his post, this would be very helpful at this point. In fact a few pics with the lever moved from one banking pin to the other with the jewels intercepting a scape tooth would be perfect. This will be of help when it comes to making the stone adjustment…if needed.
The shellac may be fine. You can test it by heating a small piece while pulling it into a fine thread.. If it pulls fine then it’s probably good.

Bob

Bob I just remembered that this thread began with two pictures of the pallet fork in place – one with the form resting on the left banking pin, the second with the pallet fork resting on the right. These show the escape wheel teeth well as well. Were you wanting to see these with the banking pins out all of the way?

Thanks,
Tom

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