Repairing a self-winding Bulova Watch

Published: September 29, 2013

Watchmaking is really just solving mysteries. When we get a watch, we get to see two sides of it. The first is the exterior of the watch. This includes the case, the crystal, the dial, and anything else you can see without opening the watch up and actually looking at the movement. Often, this matches the second side of the watch. As I foreshadowed, this is the “inside” of the watch – the movement.

I took in a man’d Bulova Watch recently. It was a 23 jewel, self-winding watch from the 1950’s. The customer had purchased the watch recently, and it had run when he bought it.

After I uncased the movement, I could see that this watch had a mixed history. The dial and hands both had some rust on them in places, and there was some definable corrosion where the case back met the case. None of this was insurmountable. While I can’t remove rust from a dial without refinishing the dial, I did brush the rust off the hands and thoroughly clean the case.

However, this didn’t do anything to address the issue of the watch not running. I examined the watch under my loupe. The movement seemed clean. Also, there were zero service marks inside the case. Was I the first person to service this watch? No – I saw some geezer marks on the balance cock and the train bridge.

Looking more closely, something immediately grabbed my attention – there was a small hair laced through several of the hairsprings coils. The hair didn’t seem to be much thinner than the actual “hair spring” (also called a hair spring). I removed the hair using a pair of fine tweezers and the watch immediately came to life.

“Well, that was easy”, I said to myself. While I still planned to service the watch, I was curious how well it would run in its current state.

I put the customer’s Bulova onto my timing machine. It was out of beat, and it was running several minutes a day slow.

From hereon, the watch simply required a standard servicing. I fully disassembled the watch, cleaned every jewel and pivot, oiled the watch, reassembled, out the balance into beat, and tested the watch for a few days. It ran well, and I know the customer will be pleased.