Waterbury Open Brocot Escapement

[HectorLooi]

I recently bought this non-working movement to practise on an American-made movement. 

So far I've only worked on English, German, Japanese, Korean and Chinese clocks. And if this movement is typical of an American clock, I'll be staying clear of them in future.

It has to be the most watchmaker unfriendly design I've ever come across.

So, back to the clock. It's a Brocot escapement with ruby pallet stones. And both of them are broken.

I managed to disassemble everything except the two mainsprings because there is a wheel that goes through the bottom plate and is held there by a pinion. 

So far, I've sprayed it with WD40 and left it overnight. I've tried heating it. I've tried using a gear puller, I've tried tapping it out. 

I haven't tried hammering it out yet because I can't seem to find my crow's foot anywhere. Must have walked away.

Any suggestions other than hammering it off? Thanks in advance. 

[watchweasol]

Hi Hector,  I have always liked the brocot exposed escapement, bad luck that the rubies are broken though.  Have you tried a little gentle heat on the pivot to maybe loosen what ever crud is holding it.  As far as I know it should just lift out, how tight is it, will it move sideways from the vertical one or two degrees or is it ridged.

[HectorLooi]

39 minutes ago, watchweasol said:

As far as I know it should just lift out, how tight is it, will it move sideways from the vertical one or two degrees or is it ridged.

I've heated it with a microtorch and it wouldn't budge. It doesn't twist in any direction. 

I'll try looking for my crow's foot after dinner. I know as soon as I order a new one from Cousins, it'll show up.

[watchweasol]

Hi it sounds well seized in if no side shake at all.  Good luck.

[KarlvonKoln]

Following (because I like the Brocot escapement, and because I've had trouble working on American clocks also).

[oldhippy]

This wheel should be friction tight so it should come off it could be held on by a pin or a clip, then the wheels holding the springs will come away from the plate.  The pallet arm has been soldered to hold it together. Your biggest problem is the broken pallet stones, they are normally held in with shellac, but you have to have both at the correct angle for enter and escape of the escapement wheel teeth. Also you will need the correct size of pallet stone. This repair is for a person who has had a lot of experience working with  brocot visible escapements.  

[HectorLooi]

Couldn't find my crow's foot last night. So I improvised.

I used one of my smaller bearing pullers and pushed on the pivot of the wheel. At the same time, I heated it with a microtorch.

It still refused to budge. Every few minutes I'll tap on the screw of the bearing puller and tighten it to take up any slack. Heat... tap... tighten... repeat.

It finally came off after dinner.

[watchweasol]

What state is the pinion in is it clean marked or burred.

 

[HectorLooi]

I have been using a homebrew cleaner for this. No actual measurements used. Just mix it up by feel. A dash of commercial cleaner, some dental ultrasonic cleaner, shot of acetone and splash of alcohol.

Seems to work. 

 

4 minutes ago, watchweasol said:

What state is the pinion in is it clean marked or burred.

 

Looks ok.

[oldhippy]

I always used Horolene clock cleaner.

[watchweasol]

Considering how well it was seized it looks in good condition.  Is the bush / bearing ok too.

[HectorLooi]

3 hours ago, oldhippy said:

I always used Horolene clock cleaner.

I'm not sure if Horolene is available here in Singapore. I'll check with my supplier tomorrow. 

 

3 hours ago, watchweasol said:

Considering how well it was seized it looks in good condition.  Is the bush / bearing ok too.

The bearings came out practically unscathed. The pivot has a small nick. I don't think it was caused by me because I didn't wedge anything under the pinion. I'll try polishing it off tomorrow. 

Someone sprayed lacquer all over the plates and some of the wheels. It is sticky to the touch.

The angle of the broken ruby pallets also don't look right. I think someone meddled with them.

[HectorLooi]

After 4 days of cleaning, polishing, pegging, pivot polishing, French chalking.... this is what I got. 

The cleaning was a nightmare. Whatever lacquer was sprayed on it, was sprayed over the existing dirt and grime. My cleaning solution became gummy. Just dipping my fingers into the solution would result in coating them in a sticky substance that doesn't wash off with soap. I had to use orange solvent to remove it everytime that happened.

I still haven't replaced the pallet stones yet. I'm thinking of replacing them with steel ones first, as I'm not sure if the clock would run.

One strange thing I noticed is the hammer is facing the wrong way. I tried turning it the right way round but there was a lot of resistance. Would it come out of the factory that way?

[oldhippy]

There is a possibility the hammer is from a different clock movement.  

[HectorLooi]

Attempting to make my own steel pallets. I'll trial them tomorrow then remove and heat treat and polish them.

[oldhippy]

So far they are looking good. Have you worked out the angles for them or are you going down the road of trial and error, what are you going to hold them in with while you test the escapement before you fix them permanently.   

[HectorLooi]

I wished I had a clock depthing tool. Putting in and taking out the pallet fork is a real pain. It's like one of those Chinese interlocking rings puzzle.

I was planning on fixing it in with shellac then adjust them in-situ, checking the locking depth. I'll use a soldering iron set to about 150°C to reheat and soften the shellac, then twist and adjust the depth.

Any advice would be greatly appreciated. 

[HectorLooi]

I also watched this video on how to set the pallet jewels.

 

[oldhippy]

You need to have the new ones you have made nice and tight for there respective holes so tight you have to tap them in so they can hardly move, Rodico might help. If they are nice and tight smooth jaw pliers are all you need for adjustment. 

[HectorLooi]

I should have made them tighter but I followed the dimensions of the old jewel fragments. I put a drop of loctite to seal the gaps and managed to get them tight enough to adjust the angles and got the escapement to work. The drop on both the exit and entry pallets are incredibly small.

I'll use a slightly bigger pivot wire to make a new pallet with a wider base but maintain the same pallet diameter. 

This project was a real learning experience.

[oldhippy]

Providing the pallets are the correct dimension for the escapement to work the rest can be bigger for a tight fit. I'd forgotten about loctite. Yes it can be difficult, I remember I spent a complete afternoon restoring the same type as you have. So good luck in your quest I'll keep my fingers crossed for you.  

[HectorLooi]

On 5/3/2023 at 7:56 PM, oldhippy said:

So good luck in your quest I'll keep my fingers crossed for you. 

I made another set of pallets and have the movement working at the moment. But I have a few questions. 

If I set the pallets according to classic Brocot escapement theory, i.e. with the flat surface in line with the centre of the escape wheel, I can't get the escapement to unlock. But if I turn the pallets a little off, the escapement seems to work fine. Is this an acceptable practice? 

When the movement is level, it is definitely out of beat. It doesn't appear to have a slip clutch, how do I correct the beat?

I'm currently using a pocket watch as the pendulum. I only have the movement, without a case, hands and pendulum. I have no idea what length pendulum to use. Do I  have to count the teeth in the gear train to determine the rate and then calculate the length of the pendulum based on the period?

[oldhippy]

To get it in beat you will have to bend the crutch. Are you sure all the teeth on the escape wheel are good and no sign of wear, no burr on the ends and the pivots and pivot holes are all good. It might be due to it not having the correct pendulum. If all is good I wouldn't worry about it.

 

Use this to  get the right length for the pendulum it will save you doing all the math. 

https://theindex.nawcc.org/CalcPendulumLength.php

[HectorLooi]

The movement has been running strong for half a day. The pocket watch that I used as a pendulum is surprisingly quite close to the correct pendulum. The movement is about 30 minutes slow over 12 hours.

There is very little wear of the movement. All the pivot holes look ok. The pivots had rust which I have polished off and burnished.

I will keep a lookout for a suitable case, probably a quartz conversion abomination and rescue it.

[oldhippy]

These movements have what is called lantern pinions so the pivots do not need to be as well fitted in the pivot holes, but if it is obvious the hole is to big or worn then work will need to be carried out, unlike the fixed leaved pinions that you have in most other clocks such as the French type of movements. The weight of the pocket watch will give you an idea of the weight of the pendulum