Wednesday, January 11, 2017

Scottish Longcase Clock - Repairing a Calendar Hand

This was a longcase clock that I cleaned and repaired for a client. The clock had several small problems, and it badly needed cleaning, but I wanted to show how I repaired the calendar hand. I find that a fair number of clockmakers can do simple hand repairs like this, while a lot don't. There is nothing really too difficult about these repairs, but you do need a bit of patience and a small bit of artistic talent to do a nice filing job that isn't too lumpy or crooked.

As received, the clock had the original second hand, and part of the calendar hand (the centre) with both ends poorly patched-in. The hour and minute hand are later replacements.

Before. This shows the original second hand at the top, the current calendar hand (as received, with ugly patches on both ends) and some newly cut pieces of brass for the repair. All I did was find brass sheet that was the same thickness (or close) and then trace it and cut the pattern using a jeweler's saw.

The second step is to de-solder and clean up the existing hand. If this hand did not have a tiny threaded centre, plus some decorative punch work, then I could have cut an entirely new hand, but the chances of matching the old threading are slim to none. Once the hand is ready, the new patch pieces get trimmed to fit, filed to size, and then soldered in place with two small patch pieces on the back.

I just used regular solder. There is no real need to use silver solder here.

I did not try to copy the punched design on the repaired section, but I did antique the brass to make everything blend nicely together.

Also note that the original hand is quite roughly cut, so you can get away with quite a bit of small mistakes.

I'm proud to say that the client was very happy with the repair.

PS: the taper pin in the two photos above was just a temporary one. I don't leave them that long, and the finished one was steel, not brass.

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