An assortment of 'cleaned' parts that still show dirt

Clock Repair 101: I Finished “Cleaning” the Clock

In my previous post I showed the early results of my cleaning of my Goodwill clock by hand. In this post I show why cleaning by hand isn’t really very effective at removing old oil and dirt.

After a few hours of scrubbing parts with SOS pads and toothbrushes, then rinsing in water – twice to get all the soap scum off – then rinsing in alcohol (wearing gloves this time), the clock parts are all “clean”.

Update: Don’t use SOS pads or steel wool, because those leave little bits of steel wool everywhere. Instead I now (May 2021) use dish detergent and a soft toothbrush for that step.

The clock parts after cleaning by hand
The clock parts after cleaning by hand

I’m happy with the results of this first try: the clock is a lot cleaner than it was.

At the same time, I noticed a few things that an ultrasonic cleaner would likely clear up.

a delicate part, with gunk remaining on the pinion
a delicate part, with gunk remaining on the pinion

In the photo above, you can see gunk remaining on the pinion (the little gear) of the fly (the speed control for the striking). Because of the delicate weights in this part, I was reluctant to scrub it.

Also, in the photo at the beginning of this post, you can see all the tiny parts that aren’t cleaned much at all. Again, because they were delicate, and easy to lose, I only gave them a little swish in alcohol instead of the full cleaning.

gunk and water remain under a clip like this
gunk and water remain under a clip like this

Another class of poor cleaning is a lack of disassembly: in the part above, I don’t yet know how to remove the spring clip, so I cleaned the part without removing the clip. Dirt and rusting water will remain under the clip regardless of how I clean the assembled parts. You can even see some rust on the gear, possibly from a previous, similarly-incomplete cleaning.

In my next post, I figure out which gears are part of the time train vs. the strike train, and calculate the ideal length of the pendulum.