Old Balance Bridge Repairs

Most 18 size Elgin watches have a plate design where the balance wheel is outside the rest of the works, the rest being covered. We see this design called both "full plate" and "3/4 plate". At any rate, a balance bridge supports the upper pivots of the exposed balance wheel on these watches.

If the pivot does not move freely in the upper pivot, then the watch will not run well, particularly when laying face up. The causes can be a worn, damaged, or incorrect upper jewel, damage to the balance pivot, or a warped balance bridge.

One thing I see an a lot is a makeshift adjustment to the balance bridge, usually intended to make it sit slightly higher with the idea of giving the balance more freedom. The adjustment consisted of using a graver to make "digs" or burrs into the plate creating raised spots, under the bridge.

This repair can be tricky to deal with.  In many cases fixing the original, actual, problem by, for example, replacing the jewel or staff, and then removing these raised spots leaves things in good shape. But many times I find that the bridge also appears to have been deformed slightly. The movement may have been dropped, landing on this part, or it may have been deliberately manipulated.  Getting everything to line up again on this critical part is difficult.

This watch, a grade 336 Elgin pocketwatch, is a particularly troubled example.

In this case there are old burrs on both the plate and the underside of the bridge.  Also they have both been undone with a file, and redone in the past.

The upper balance jewel on this watch was cracked and worn oblong. These burrs are likely old attempts to deal with that without replacing the bad parts.

As annoying as this is, it's just the nature of the old watches. When these watches were in use, they had to be repaired as best they could be, sometimes by their owners, or whomever was available, and with the tools at hand. Factory parts in those days could be rare and expensive, so they did what they could with what they had. It was also not unusual in the 19th century for people to carry watches that were off by 10 or 20 minutes a day, or worse. But they were better than sundials at least.