Birks – Skeleton Pocket Watch – ETA 6498

Another day, another watch 🙂
Mario gave me his personal pocket watch to have it cleaned. I don’t get to work on
this movement regularly, but, for most watch repairers, this is where it started. Most schools
will start off with a micro-mechanics course. Which is where we make parts, very small parts. For this particular movement (ETA 6497 – 6498) we had to make a setting lever jumper. In other words, this part is what separates the winding mechanism from the hand setting position when you pull out the crown on your watch. After making the part, we had to test it on an actual movement. I’m happy to announce, mine worked. When the micro-mechanics course finished, we start working on movements, and we start on this particular one actually. Most probably because it’s a rather large one, built like a tank and easy to work with. Well, in the beginning they weren’t that easy to work with. Although these are rather large pocket watch movements, they certainly seemed small back then.
Our first task was to set the jewels properly. First we would start off with the center jewel until we learned to perfectly place them, then each and every other jewel in sequence. After learning to do that properly for several weeks, we moved onto oiling the pivots. Again, doing that for several weeks. Next, we took the movements apart, cleaned them, and put them back together several times a day, and for several weeks. In other words, I could take this watch apart, clean it, properly adjust the jewels with my eyes closed 🙂
To be honest though, I never did work on a skeleton 6498, so, this will be fun 🙂

Time to put it on the timegrapher and see what I’m dealing with. Not great but certainly not horrible.

Now it’s time to take it out of the case.

First thing is first, always remove the balance.

Next up, is to remove the ratchet and crown wheels. That’s quite the interesting build up of a dark looking grease.

Then, I turn the movement over, and let down the mainspring, followed by removing the setting lever jumper, stem, sliding pinion and winding pinion, two intermediate wheels and last but not least the yoke and yoke spring.

Again, I turn the movement over, and start by removing the pallet cock and pallets, followed by the barrel and gear train bridge.

Cool!

And, there it is, the 6498 in all it’s glory, cleaned 🙂

Normally, I would start off by doing the regular chores by installing the mainspring in the barrel and whatnot. But, this movement is rather large, so, all the components and parts didn’t fit into my watch cleaning basket. So, I had to do it in two runs. I had to clean the movement then the mainspring in a second run. Instead of waiting, I just went ahead and started installing the keyless works and motion works while waiting for the mainspring to be cleaned.

There we go, the mainspring is now cleaned and oiled and now re-installed in it’s barrel.

I start off with properly seating barrel, centre, second, third and escape wheels.

Followed by their respective bridges. Looks much cleaner eh!

Then, the crown, rather and click are installed.

And voila, a much better amplitude, beat error and rate 🙂

Last up, to set the hands and put it back in it’s case, and ready to use.

I hope you enjoyed reading my most recent post as much as I certainly did working on this pocket watch.

Cheers

Chris Marcellin