Small Gustav Becker pallet lock up

[David S]

Hi Jurgen suggested that I move my thread to the repair forum. I originally started it in the general clock forum as "help identify small GB clock". This clock has been running for 9 days, so I decided to wind it. Now it has been stopping periodically and when it does the pendulum appears locked since one pallet is sitting on top of an escape wheel tooth. This has occured on the entry and exit pallet. I have marked the tooth, but no pattern there. This clock did this before I took it apart. Also it has been worked on previously and had some not quite so professional repairs. I will include a few previous pictures here.

Before I start trying to change anything I would like to get some suggestions.
Thank you
David

 

[shutterbug]

It looks like the pallets are pretty rough, and that might be at least part of the problem. They need to be really smooth and highly polished. The exit pallet might be sitting a little skewed, but it's hard to see in the photo. I think I'd pull the anchor and fix the polishing problem first, then with the anchor still out test the EW action. It should start turning within two turns of the key, and when stopped with your finger, easily start turning again. If there's a problem there you'll be looking at power problems in the time train (center).

 

[David S]

Shutterbug. I think I may have found my problem, embarassing as it is. Like I mentioned, after service this clock has been running for 9 days just fine. Yesterday I decided I should wind it. For the past few weeks I have only been working on T&S clocks...get where I am going with this...I wound the two outer arbors....forgot the center (time arbor). I figured something was up since this morning it would just run for a minute then stop...no lock up. I will let it continue to run.
Regarding the pallets, they are black and appear to be that way unless someone replaced them with black pivot wire??. I will continue to monitor, and if it acts up I will certainly follow your advice. I hope I haven't started a false alarm, but it does need to be wound up. BTW when I put it back together and checked the trains out with just a bit of power they ran just fine.
David

 

[shutterbug]

Well, it happens to everyone eventually. It's good to get it out of the way early in your career.

 

[soaringjoy]

The original "Clock Thread" had a jinx from the start, sort of.
We had real troubles getting that movement worked out...
Compliments to David, he did well on it!

Here's where it all started:

https://mb.nawcc.org/showthread.php?84986-Help-identify-a-small-GB-clock

 

[David S]

Thank you Jurgen, however it was your comment in the previous link post #7 that gave me confidence. I have it back on the test wall now and it has been running for a few hours...let's hope. And of course thank you to all who contributed.
David

 

[Scottie-TX]

Two things here get my attention:

This clock did this before I took it apart. Also it has been worked on previously and had some not quite so professional repairs.

" . . did this before I took it apart"
If it did this before and nothing was done to address this problem, I'd expect it to do it again on reassembly.
". . . . been worked on previously"
Am I seeing things? Looks to me like teeth have flat tops. Do they? You started by saying it stopped with both pallets landing on tips of teeth. They could not do this if teeth didn't have flat tops. Appears maybe wheel was trued by "tipping" . This leaves the teeth with flat tops. This causes two problems: It robs you of some lock. Lock must be decreased to accomodate less space between teeth and 2. Pallets can land on top of teeth.
If they are flat topped, I'd file the INACTIVE side of each tooth until it comes to a point and readjust lock.

 

[David S]

Hi Scottie. I should clarify regarding the pallets. Both never did land on the top at the same time. I noticed that the exit pallet did, and the entrance did at different times, and when it finally "died" they would just be between teeth.
When I tried to run it prior to doing anything to it, I had noticed the same thing. However when I let down the springs and took out the verge to test it some more prior to dissassembly it would hardly run...no power. The pivots / bushings at the top of the drive train were full of thick black poop. Just to be sure that was it, I did a brush clean with naptha to try and dislodge as much crud as possible. That made a huge difference it now would run with very little wind on the arbor. At this point it looks like when there is no more spring power left it is a bit of a crap shoot as to how it will stop.

As posted previously, it has been running now for 6 hours (once I wound the time spring) and is back on my test wall. And also as I mentioned it did run for 9 days prior and after the overhaul.

David

 

[Watchfixer]

I have a travel clock with pin pallet escapement wheel impulse faces are rough that if balance wheel goes backwards while pin still sitting on the impulse, caught pin and held pallet fork from rotating, caused fork to overbank because of both pallet and staff arbors so slender and flexible. Fixed that with a good EW from another movement.

Check that yours are smooth on the pallet pins and EW is good, not blunt or rough.

Cheers, Watchfixer

 

[Scottie-TX]

Poor choice of words: Yeah, understand. It didn't stop with both pallets resting atop teeth. That's not possible.
Now about this gunk you removed afterwards: It is not common to have this after disassembly and cleaning. Did you completely dismantle this movement? How did you clean it?

 

[David S]

Scottie before I took it apart I tried to figure out what was wrong and play with the movement since I had not worked on one of these before. I wouldn't run much and would sometimes lock. I let the springs down, then with a brush and naptha cleaned as much crud out as possible. Oh I also took the verge out and with a bit of power on it would hardly run, even with a few turns. Then I cleaned it with the brush. After that it would spin freely with just a turn on the time arbor spring. I did not put the verge back, but proceded to take it all apart and clean all the parts separately. Cleaned it in the US, then rinse and pegged the bushings etc. Like I mentioned this clock has been worked on before and some of the cams etc on the outside of the plates looked like they have been removed with vice grips since they were chewed up in places, and another complete wheel had been replaced or repaired since it was now too short so a long bushing was put in to extend into the movement from the inside of the plate to support the pivot.
It was running for 9 days before I started this thread. And it does look like a false alarm since once I remembered to wind the time spring it is still running this morning.
This clock has very small diameter pivots, much smaller than I am used to , and I would rather not mess with it more than I have to. I was concerned about busting one trying to get them all back in place again.
David