Tuesday, December 31, 2013

Daniel Pratt Jr. Clock Restoration - Part 2 of 3

Movement Restoration & Cleaning

There seems to be a lot of confusion and misinformation when it comes to wooden works clocks.

In general, wooden works clocks require NO LUBRICATION, with the exception of the escape wheel and verge pallets on the front of the movement. A further exception can be made when a wooden movement has BRASS bushings.

If the movement has ivory, Delrin (added at a later date), Lignum Vitae (added at a later date), or plain oak (wood) bushings, then it needs no oil, and certainly no graphite.

The only maintenance needed on these movements are occasional tooth repairs, and gentle cleaning (mainly dust removal).

In the case of this particular clock, some more heavy-duty cleaning will be required since half the movement was completely smothered with greasy graphite lubricant.

I was grateful that the strike train was spared from this treatment, but the time side had enough graphite in it to make a few pencil leads.

In the following photo, the strike train has been removed and set aside. Unfortunately, most of these photos were taken on the kitchen table under bad yellow lighting, so it may be more difficult to see all the details.

If you look closely, you may see that all the wheel teeth as well as the pinion leaves and bushings are all coated with graphite.

The time train also had two less than desirable repairs, made using SCREWS with the heads clipped off. This is an absolutely AWFUL repair.

These two broken teeth were from the motion works inside the plates, so luckily they were not under a lot of force.

Cleaning off the graphite from the plates was fairly easy. I simply used a cotton rag (in this case an old tube sock) and some warm water with a drop of dish soap. This, combined with some good ol' fashioned elbow grease did a wonderful job. Here's a half-and-half before and after. Note that the time train has been bushed with brass bushings. I'm not sure if these are original to the movement or not.

Interior of the front plate before and after cleaning.

Some staining remains, but 90% of the graphite was removed. Cleaning the bushing holes was the most torturous part. It involved nearly a dozen q-tips PER BUSHING in a combination of dry and wet (soapy water), plus about 5-6 toothpicks to peg the hole.

Here you can see the mess that was done to the time side great wheel. The cleaning procedure for all the wheels was quite different than with the plates.

To clean everything as thoroughly as possible, I started by scraping off the excess blobs with toothpicks and q-tips. After this, the wheels were scrubbed with dish soap under cold running water, using an old tooth brush.

A lot of people seem really paranoid about completely wetting or submerging wood, but there really isn't much harm in it, so long as the pieces are wetted evenly (because if you wet only one side of a board it may want to cup), and dried thoroughly. I have personally seen timbers (white oak planks) that have sat at the bottom of the St-Lawrence river for over 100 years, and these were brought-up, dried, cleaned, and milled into mouldings for a house You would never have known they were once at the bottom of a river. A little bit of water won't harm wooden gears, and I know of a few other restorers who also wash severely soiled pieces this way.

Here is the motion works gear after cleaning, and tooth repairs.

There are traces of graphite left, but overall, it's pretty decent.

Likewise, here is the time side great wheel after cleaning. Note that this tooth repair was a previous repair. I removed the excess blobs of glue, and stained the tooth to improve the appearance of the repair.

Here is the newly rebuilt leaf pinion, done in cherry, with close to the original profile.

The time side is now fully functional, with all the teeth in good (or repaired) condition. The same can't be said of the strike side. The strike side suffers from three problems:

- 4 broken teeth to the countwheel
- All 6 leaf pinions sheared off from the countwheel advance pinion
- Both strike levers are missing (something I had never noticed until this past week)

The pinion can be rebuilt, the countwheel teeth repaired, and the strike levers remade, but not at this point in time. I don't plan to run the clock, so for now, I'm content to leave it as-is.

Here's a short video of the bell striking.

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