Handy Hints

Article by: Andrew Markerink

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18th century English longcase and bracket clock hands are things of beauty all by themselves and can show the quality of the workmanship in the creation of fine quality clocks in the period. A specialist generally made hands that we now refer to as a hand maker and who obviously possessed many skills that enabled him to craft steel into finely detailed hands.  The fact that we can today reach into a draw and fit a new 4/0 saw blade out of a packet would not have been a simple task in the 18th century and presumably involved a substantial investment in time and effort.

The simple tasks that we take for granted would have taken a major effort. The effort taken then to acquire from a saw blade make a number of hand made blades or to possibly have made the blades yourself wasn’t the end of the detailed work that was undertaken by these 18th century clockmakers. Simple close inspection of early pairs of hands shows that great care time and creativity was used in the creation of this important item for the clock. Hands are often fettled and engraved and the lightness and balance are amazingly accompanied by their functional strength.

I have often thought that there must have been a rule in hand making where hands must look like they are fragile but always be strong. Whether this rule existed or not the effect is the same hands were both extremely fine and strong to enable function.

Despite the endeavors of these hand makers to ensure that the hands they created remained intact and functional there is always the chance that the hand could become broken either by misuse or fatigue over time. It’s the broken hands and their attempted repair that we see in the workshop that I find most disappointing.

I recently had an example of a second period 18th century style longcase come in that had a poor quality repair done to the minute hand. The repair resulted in what was once a well balanced hand becoming a blob of black mess.

The hand had been broken in 2 places and the attempted repair was made by lead soldering a piece of brass to the back of the hand and then painting the hand black. The result can be seen in the picture looks terrible and makes the once fine detail of the clock and dial a black blob that looks nothing like its former design.

Repairing these hands so that they look like their former shape and function well is not simple but not repairing them makes the clock look as though it has been poorly cared for and offers no respect to the quality of the makers work. The alternative of lead soldering a piece of bras to the back of the hand I am sure takes as long to do as repairing it in a more sympathetic manner. Several easy steps can be taken to accomplish the repair, which will provide an excellent result.

The first step in the repair is to remove all of the lead solder and the backing plates that have been fitted. It is crucial that none of he lead remains because any residue will weaken the soldering joint that will be applied to correctly repair the hand. I use a three sided scraper and razorblade to achieve this end as it allows you to remove the lead without removing any of the original steel. I don’t recommend using an emery paper as this will indiscriminately remove steel and lead making the hand thinner and even hander to return to functional strength. Scrapping away the excess lead is easy as the lead is soft and the steel hard so the lead is the only part removed. Using a razorblade also allows fine access into corners and along the sides of the hand.

Secondly we need to prepare the two parts of the hand to be reattached. To simply but join with solder will not provide a bond with sufficient strength to allow a return to function. I bevel the point at which the hand is to be joined. The angle I choose is relative to the width of the solder joint and can be anything from 45 degrees to 30 degrees with the steeper angle being used for narrower hand joints.

Thirdly it is crucial to flux all parts to be brazed together including the end of the brazing rod. I do use a high silver content brazing rod and not silver solder as I find it achieves a better bond and it can be chemically coloured to match blue steel in the finishing process. Once the hand pieces have a bevel applied that will enable a solder joint to be made we have to be able to hold the pieces of the hand so that can be held securely.

Fourthly I find it best to apply solder to the points to be joined before attempting to bring them together this reduces the potential for oxidization and allows some maneuverability when bringing the pieces together particularly when the hand is fine and has multiple breaks.

Finely reflux the areas to be joined and braze them together. I have repaired possibly 20 pairs of hands using this method and have had great success. If the joint at the bevel is good it will only leave a very small line, which can be coloured after the hand, is blued or oxidized using various chemicals that are available for this process. (Liberon in QLD have several in their range).

The result in this instance left a slightly larger solder residue, which I chose to paint matt black but it would have also been possible to chemical colour the hand so that it looked like aged bluing. With the bras plate removed the hand and dial both look substantially better.

Article by Andrew Markerink

Posted in: Tick-Talk

About the Author:

For over three decades Andrew and his staff at Master Clockmakers have been involved in the restoration and conservation of timepieces from historically important clocks such as Sydney Town Hall and the clocks for Sydney Central Railway to small intricate ladies watches made by watchmakers such as Patek Philippe.

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