Eternasonic (ESA 9162)

[bobtheterrible]

My first ESA 9162 movement.

Bought as a non-runner. It hummed but there was no movement in the hands.

Turns out there had been a battery leak (not clear from the description, grr...) which had spread to one of the modules and the index wheel.

I cleaned plate with some bi-carb and water. The module had suffered heavy pitting on its contacts so I replaced it for a spare left over from another project.

The index wheel was problematic. After cleaning and soaking in essence of renata the crystallised battery contents was still solidly attached. It was also covered in brown "gunk" which I could not identify. Assuming it was a lost cause I put it back on the module plate and ran it through the sonic cleaner for 15 secs. I checked it through the microscope and  miraculously it seemed to work!

Cleaned up the case and crystal (original) and put it on a home-made brown leather strap.

Quite pleased!

Edited December 31, 2024 by bobtheterrible

[HectorLooi]

Nice work.

I find that an acid works best for cleaning battery juice damage. The battery juice is potassium hydroxide and is very alkaline. Sodium bicarbonate is also alkaline, so there is no reaction.

I used to use vinegar for neutralizing battery juice but I found that phosphoric acid works even better. The phosphoric acid comes in the form of a rust remover bought from a hardware store. I dilute it 1:1 and brush it on with a size 00 artists brush. The acid works immediately and bubbles can be seen. It also brightens up brass and removes rust, the green corrosion crystals and stains from the plates, without any hard scrubbing. Do not leave the acid on for too long, as the brass will start turning reddish from "dezincfication". It usually takes less than a minute. I then wash the parts immediately in distilled water. 

I have managed to revive many shorted circuit boards this way. 

[bobtheterrible]

@HectorLooi I did wonder about that. The bicarb worked better than just water but was worried about putting acids on the movement parts. This is good information I will use on other projects. Thank you!