Brockbank & Atkins With Platform Escapement

[rodabod]

Just about to clean this one, so thought I’d share some photos. 
 

This maker made some ship’s clocks but also retailed similarly built clocks for the domestic market. The finer examples had a fusee and compensated balance. This one omits the fusee for an intermediate wheel and has a plain balance. However, it’s still quite nice in my opinion. 
 

 

[rodabod]

Dial off. 

[rodabod]

Jewelled lever. 

[KarlvonKoln]

Wow, that clock exhibits some seriously robust and rugged construction.  It must really weigh something.  Everything looks so precise.  I am not often privileged to see this level of quality in most modern clocks I've opened or worked on (which admittedly is not many; clocks are not my forte).  I enjoy seeing craftsmanship like this. Thanks for the pics.  

[rodabod]

Jewelled chaton endstones are removed from escape wheel cock, platform, and balance cock. 

[rodabod]

Front plate removed. You can see a quite nicely constructed Geneva stop-work on the barrel. The pivots are chunky!

[Willow]

just have to echo what KarlvonKolon has said lovely well made clock

[watchweasol]

Yes a quality piece and will be a pleasure to work on. Note the thickness of the plates and the fact they are pinned not screwed a nice clock.  

[wls1971]

I have a Brockbank and Atkins bulk head clock a fusee with maintaning power, large temperature compensated balance platform the plates are the same shape, a very heavy built movement. Does it have the original key, movement, dial and key numbers should all match 12617 is the number of my clock which I would think dates it to about 1880's. Does this have a stand they often have a stand that makes them look something like a napoleon hat clock when put together. 

[oldhippy]

A very nice little movement and it should keep very good time. 

[rodabod]

2 hours ago, wls1971 said:

I have a Brockbank and Atkins bulk head clock a fusee with maintaning power, large temperature compensated balance platform the plates are the same shape, a very heavy built movement. Does it have the original key, movement, dial and key numbers should all match 12617 is the number of my clock which I would think dates it to about 1880's. Does this have a stand they often have a stand that makes them look something like a napoleon hat clock when put together. 

Thanks for the info. It does have an original key, albeit it’s a number of digits off the number on the dial. Not sure how, unless it was owned alongside others and mixed up. The movement and dial numbers match, and it does also have the wooden stand which makes it look a bit like a Napoleon Hat. I’m glad you mentioned the stand as I thought it was aftermarket and might have binned it!

[rodabod]

I’ve had a look at the pallet jewels under a microscope which look good. Escape wheel also looks fine as far as I can see. 

The only issue I can see is that the original garnet lower cap jewel for the balance has a slight amount of pivot wear. If you look at the photo below, you can see the wear which is around 0.1mm wide. I’m tempted to leave it as-is since the cap jewel is a really thick slice of garnet and I can’t imagine managing to find an original. I also don’t really want to spoil the originality. 
 

If the cap jewel does noticeably affect the performance then I think I will possibly either try an additional thin ruby cap jewel on top of the original chaton, or I could turn a new chaton with a ruby jewel. Both options would be reversible. 
 

 

[rodabod]

I’ve polished the agate jewelled chatons on glass with diamond paste. Removed around 5/100mm from the surface. 
 

Agate doesn’t seem to polish very well to me. It’s a bit crumbly. However, they are now free of the signs of pivot wear. 
 

I’ve decided to oil all of the pivots and cap jewels with HP1300, so will see how that works out. I think the balance is too heavy in weight to use a lighter oil. 

[oldhippy]

What is HP1300?

[rodabod]

7 hours ago, oldhippy said:

What is HP1300?

Pretty much the synthetic version of D5. I think it uses the same formulation as 9010, but is much thicker. 

[rodabod]

The next issue which I have, which was possibly predictable is excess end-shake on the balance which I believe is causing the balance spokes rub slightly. I was hoping the lower chaton would seat itself with the same distance from the jewel hole, but evidently not. This may be since the chaton is cone-shaped, so it’s not sitting any closer than prior to being polished. 

[rodabod]

So, I used my jewelling set to correct the balance end-shake by increasing the depth of the chaton which carries the lower cap jewel.

I also noticed that the same needed to be done for the escape wheel’s lower cap jewel as the polishing of the stone had caused the alignment of the pallet stones and escape wheel teeth to shift slightly. 

Finally, I rounded the lower balance pivot and burnished it. I’ve added some photos below to show the stages:

- Original pivot with scoring and flattened end. 

- Pivot after polishing to a round profile. I used a soft polisher to do this to avoid leaving any abrasive embedded in the pivot. 

- Pivot after burnishing with a Bergeon “pivot rounding” burnisher which works surprisingly well. 

The balance swings for a few minutes under its just own momentum now, so negligible friction as far as I can tell. I’m getting around 225 degrees amplitude which I reckon is probably reasonably for an English lever escapement, but I’d be interested to read about what might be typical for this type and age. 
 

 

[rodabod]

Here’s a photo of the slightly odd stand that the clock mounts on to make it a mantle clock. 

[oldhippy]

Makes it look in the style of a napoleon hat clock case. 

[watchweasol]

Looks very nice, clean lines.