Adjusting a wheel cock

[MikeEll]

Good morning, all.  I'm working on an old French clock movement that has mostly been running perfectly after a full strip and service.  Occasionally, it would stop, and I've traced the problem to one of the wheels in the going train.  Photos to follow, but the wheel (I think it is the 4th wheel from memory) has been mounted on an odd angle, i.e. not parallel to the plate.  It also had too much end shake, and, as a result, at one end of its end shake travel, it was slightly too far away from the escape wheel pinion; at the other end, it was too close.  Depending on where the wheel happens to be, it either slipped a tooth once in a while, or would be too close and stop the clock. 

The wheel is mounted by a cock on both ends (I'm sure there's a rude punchline deserving here  ), so a little challenging to adjust.  Each cock is mounted to the plate with one screw but located using two pins.  My question is how to go about adjusting the position of those cocks.  I've searched online to see how to go about relocating and fitting those locator pins, but I haven't found anything.

Could you offer any advice, please?

Ta

Mike

[watchweasol]

Hi Mike we definitly need pictures to determine the problem.  Sounds like it hs been done over. All wheels/ arbours should be parallel to the plate with little end shake,  ideally when the clock is powered down tipping the clock from side to side all the wheels should drop a little .

[nickelsilver]

It sounds like you have too much side shake, which would indicate a worn hole and likely pivot. Some folks do bad things like ream out the holes for the locating pins so the cock/s can be shifted to try and compensate, sounds like that may have happened too if it's visibly not perpendicular to the plates.

[MikeEll]

thanks, guys, I will grab some pics on Saturday as I don't have the movement with me at the moment.  Yes, the wheel is visibly misaligned to the plate in more than one orientation.  I've corrected the end shake but I believe the pivot holes are not in the correct place to properly position the wheel relative to the plate or the wheels it engages with.  So, if I need to adjust the position of the cocks themselves (there are two, one either end of this wheel arbour), how do I go about doing that.  As a more general question, I was interested in the procedure that should be used to mount a cock of this type to a movement plate.  e.g. how are the positions of the locator pins determined and how would you mark these out and drill the cock and the plate?

Edited January 27 by MikeEll

[oldhippy]

I need to see good clear photos before I can advise. 

[MikeEll]

This is the only picture I have for now, I’ll grab some clearer ones at the weekend.

[MikeEll]

I managed to sort this in the end.  A gentle couple of turns with a broach straightened things out.  That allowed me to move on to the next problem, a broken pivot on the escapement arbour.  I've never needed to replace a pivot before, and this is the kind of clock you don't just buy spares for....

The new pivot here is shown before polishing.  I cleaned up the end of the arbour, drilled a new pivot hole, and silver-soldered a piece of blue-steel steel into place.  Cleaned up the solder and pivot on the lathe, polished it up and fitted it to the clock.  Quite pleased with the result, which looks more substantial than the original.  The clock has been running perfectly on test for the past couple of days.  Just doing the final regulation after casing it up, and it's back to the owner.

Edited February 11 by MikeEll

[Dell]

Nice work but for future reference I just twist press fit a new pivot in the heat from silver soldering would have annealed the arbor & of course the blue steel wouldn’t be hard either just my suggestion.

[MikeEll]

Yeah, thanks, Dell. I know what you mean. I had a slight complication with this one, as I managed to break a carbide drill while drilling the hole. I was left with a much shorter hole than I wanted and couldn't remove the drill fragments. Silver solder seemed the best option, giving me a much stronger pivot. Also, as an escapement arbour, it has very limited movement, so I felt the wear issue wouldn't be a concern.

[oldhippy]

Well done. I'm sure that is not the original case

[MikeEll]

11 minutes ago, oldhippy said:

Well done. I'm sure that is not the original case

Yes, I agree.  It looks like a home-made case.  It's not really my thing, but it's an important clock to the owner.

[MikeEll]

I just dropped off with the owner, and he was pleased.  Job done.

 

 

[oldhippy]

 Another satisfied customer. Do you keep records of your repairs?

[MikeEll]

yes, I try to keep pictures and a diary of what I've worked on.  Especially since I've started using ClockMaster for regulation, I also keep a record of the movement details.  Counting the teeth on the relevant wheels gives me a target of how many beats per hour the movement needs to achieve.