Wednesday, 30 May 2012

Elgin 379 Pocket Watch Restoration

This is an Elgin 379, size 18, open-faced pocket watch with a Silverode case. I purchased this from eBay in non-running condition thinking that it would be a quick fix by the description. And of course, I was wrong. Apart from the aesthetic work on the case, the balance was in a bit of a state, and I had to replace the staff, repair the balance, replace jewels and some pivot-less wheels. This job ended up consuming 2 non-running 379s, and as I write this post the watch is running nice and strong right in front of me.

To start, the case has seen better days. There are deep scratches and small dents a-plenty. The following photos give you an idea of the starting point. This might not be a big deal for some, but at the time of writing this I am without a functioning bench motor (no polishing wheel) - the Dremel will have to suffice.

 The movement plate and bridges are in exceptional order, this photo was taken just before I began disassembling it:

I really love bimetallic balances from the start of the 20th-century. There is an incredible amount of craftsmanship and skill that goes into the manufacturing and adjustment of these components. Even though the technology in this type of balance wheel has long been superseded, there are still plenty of fine examples around. Unfortunately, this is not one. There's rust on the balance spring, the balance arms are slightly deformed and the top pivot on the staff had snapped off.

After replacing the balance staff, I placed the balance in my truing calliper. Straightening the balance arms to something approaching 'true' took quite a while, the last thing I wanted to do was apply a little too much pressure and then have to track down a suitable replacement part online..

Another problem: cracked jewels. On almost every wheel - and strangely all on the bridge (not the mainplate). Luckily these jewels are nothing special and I've got a pretty good supply of replacement pocket & wrist jewels floating about my parts draws.

The chatons that the jewels are set in can be a little stubborn. Even though they are 'held' in place by screws,  they may as well be friction fit chaton/jewels. I don't have a jewelling set, so the watchmaker's favourite tool (staking set) steps in to lend a hand.

After I mended all the tiny problems with the plate and scavenged replacement wheels and springs, the choicest bits went into the ultrasonic cleaner.

Now for the assembly. With full plate movements like this, the order that you assemble the movement in is quite important. I'm reluctant to generalise, but with most 'conventional' mechanical wind movements (at least those featured on this blog) the obverse and reverse of the movement can normally be assembled in whatever order pleases the watchmaker. However, the keyless design on this pocket watch (keep in mind that this watch was made as watch keys were just becoming obsolete) requires assembly and some corresponding manipulation of the arm beneath the mainspring barrel before the going train is installed. Unfortunately I forgot to get photos of that crucial step, but you can see the spring arm I mention just to the right of the mainspring barrel in the photo below.

With the gear train installed. After this step, the plate gets dropped on. Well, actually, it needs to get slid onto the movement at an angle whilst a pair of tweezers guide the end of the lever into the balance roller's well (ahaahahahhhhH!).

At this point the balance required more adjustment to make sure that it didn't rub against the balance cock. After I gave it an extra fraction of a millimetre to operate within, it started to tick wonderfully.

 The vastly improved, but not quite perfect (if I'm honest) case back.

I had two dials to choose from, and this was in the best condition. When you own old watches with enamel dials, you have to be resigned to the hairline cracks. This just has a few more than usual. From here on I'll just say that they add to the character of the watch.

1 comment:

  1. Thanks for sharing that :). Great work David, also I watched some of the teaching videos it is really useful and informative. It teaches how to make and maintain any watch. It is very interesting area. I love the above Watch it looks very unique and traditional. Excellent work keep it up:). N