10cracd dial up issue

Submitted by Pinout on May 13, 2020 - 10:06pm

Howdy,

I have thrown the book at a 10cracd mvmt that stops ,usually pretty quickly, when turned dial up. Appears to be an  M4 President ‘I’ . Two tone face. Serviced the watch and it runs well in all positions except dial up. Tried repeating  end stone oiling, mainspring service, shimming the Barrel bridge, a spare working balance assembly, and tinkered ad nauseum. At times, after loosening  a screw or nudging a bridge it, will run dial up for hours and look good on time grapher etc. Figure problem solved and THEN.......the next cycle is back to its’ old ways. I finally just said ‘uncle’ and put a 10coacd mvmt in the case. I prefer that movement for the beat adjust feature anyhow. But still..... Anything inherent about the 10cracd mvmt being prone to this? Still makes no sense to me. Hate to be defeated. Thanks.

John T.

JimDon5822
Posted May 18, 2020 - 11:53pm

Have you looked at the jewel under a microscope?  Sounds like there might are a small chip in the jewel.

Pinout
Posted May 20, 2020 - 12:01pm

Thanks for the advice. I’ll look a little harder at them. Did not notice anything glaring when servicing balance end stones,train jewels, etc.
Watch was stuck when I got it. Seemed to be jammed up between escape wheel and pallet fork stone. I’m guessing it took a lick.? Once free it was a tickin’ up a storm. Assumed a service was all that was needed to be a regular runner. WRONG! After service the DU issue began.......
Used a complete balance from a working spare to sub , with same DU results. Would wonder about excess staff end play (out of my league) caused by balance cock jewel position....... were it not for same issue occurring with a working balance assembly from a donor. 
I have stared at this thing under the scope and nothing jumps out at me yet. Runs great with either balance until....as you rotate the movement from DD to DU, at about 3/4 turn it will normally stop dead. Flip it back over and with  a puff of air off it goes. On odd occasion it will keep running when rotated 180 and run for hours until disturbed but will not Immediately repeat. I’ll give all the jewels another exam.
In the meantime serviced the running replacement 10coacd mvmt  upon discovery that the date change process was  stopping the watch. So far so good........
Gonna pass on non running watches for awhile I think.
Appreciate the input.

John T.
 

 

Reverend Rob
Posted May 20, 2020 - 12:31pm

Could be a lot of things. Obviously it's not the balance itself, but when flipped over, something is either touching or increasing friction. It's always about the friction...

I recently had a pocket watch do exactly this, it turned out that over the years, many clumsy hands had poked or prodded the centre wheel to make it run, and the centre wheel was now bent in several places, and the endshake in the balance made it touch in the Dial Up position only.

Another issue could be the pallet fork, if the watch had a shock, there could be issues with how it is sitting, even the pivot jewels could be slightly displaced. If the roller table touches the horns of the pallet fork, it will stop dead, or even lock up by triggering a premature unlocking. 

It may also be a pivot in one of the wheels, usually the escape wheel is the one that get damaged. It could also be endshake in any of the other wheels as well, due to jewel damage or pivot damage, or even damage to the wheel rim. Whatever it is, it manifest only when the watch is running Dial up, so imagine any of the parts and what they are doing in that position. 

Pinout
Posted May 20, 2020 - 6:40pm

In reply to by Reverend Rob

Lots of good points to ruminate on. Probably should be looking more at escape wheel and pallet since that appeared to be what stopped it in the first place. I was stuck on the balance as the issue and based on what you’ve said it is somewhere else. I may swap a few parts around here and there and judge the outcomes.

I did think it odd that.....once it stops....and I look at the roller jewel between the horns of the pallet fork.....I can sort of lightly ‘fire’ the roller  jewel at the fork by cocking the balance wheel ‘slightly’ and releasing. Seems to bounce and stop on the horn. Could be normal. Air puff works best for restarting.
 

Anyhow it is good for endless hours of entertainment. Thanks for the insight. Maybe I’ll move onto to something simpler like perpetual motion.

 

John T.

Reverend Rob
Posted May 20, 2020 - 9:11pm

Lots of endshake on the pallet fork will mean that when inverted, it could touch the roller table, depending on the endshake of the balance. I was thinking about this some more, and missing cap jewels from the train will also do this, but will be very obvious.

If the stoppage is immediate, that is, the balance stops dead, with no residual swing, that points directly to the escapement. 

Pinout
Posted May 21, 2020 - 8:53pm

RR,  The saga continues.

Well, I swapped out more parts from the functioning parts spare I have. 
Based on our conversation I was curious to swap out .....the balance once again (last time it stopped just like the original did) and this time also include the escape wheel, pallet fork and cock from the spare.

Drum roll........

The problem mvmt now performs like the spare did. Runs.
I exchanged the same list of parts from the problem mvmt to the working spare. It performs now like the problem unit. Slows way down and/or suddenly quits.

I see it as the following: the balance would seem to be ruled out by the first swap and the jewels and pivots seem to be exonerated by the total escapement swap.
That leaves escape wheel, pallet fork, pallet cock (although jewels looked good) or some combination thereof.

My money is on your suspicions regarding the pallet fork as a likely culprit. The original problem after all was a jammed up escape wheel and pallet fork. 

When I was swapping escape wheels I spun each of them on a truing tool and each one appeared to spin true with no wobble and the pivot on each end took turns on the bottom and appeared to be consistent.

Think I’ll claim victory here and move on. Will try to put the watch for model I.D.

Thanks for your help with this. Quite the learning experience.........

John T.