Technical Notes: Movement Finishing with Cameron Weiss

Here at Wound For Life, we love a great tool watch. Understanding that in most instances, a durable and robust case is one of the main components of a watch that’s going to last a long time. Today we’re going to focus on the heart of a lifetime wrist companion: the movement. We don’t need to tell you how incredible watch movements are in terms of micro-mechanics, but we do want to talk about movement finishing. Geneva stripes, snailing, etc, they all look great, but what’s their purpose? To answer this and other questions, we reached out to Cameron Weiss, founder and master watchmaker at Weiss Watch Company. He was nice enough to field some of our burning questions on movement finishing. Below, you’ll find our questions and his answers. Thanks for the help, Cameron.

What finishing techniques do you consider most important for improving the accuracy and precision of the movement?

The burnishing of pivots is the most important finishing process for accuracy.

Ed. Note: Pivot burnishing is the act of removing imperfections from pivots to improve their fit in the pivot point. If a pivot point has too much friction, the associated gear or wheel will not rotate properly. Here’s an excellent video from master watchmaker, Roger Smith, demonstrating pivot burnishing. Notice how the unfinished pivot allows the jewel to move up the shaft, but only to a certain point. After some work, the jewel fits perfectly.

At what point do these finishing techniques cross over from functional to aesthetic?  

Movement decoration was initially developed for functional reasons and has remained due to its beauty and tradition. Blued screws, which is a forced surface oxidation that inhibits rust, is not as important today with water resistance cases as it was when developed for open back pocket watches. The same goes for the perlage and striping surface finishing on plates and bridges that actually creates a rough surface with tiny burrs that “grab” dust particles and keep them from migrating into the lubricants in the jewels and pivot points.

What finishing techniques do you perform in-house? By hand? By machine?

Bridge and plate surface finishing, engraving, and plating. Also some heat treating, as well as polishing.

All finishing is performed by hand with the assistance of very specialized machines set up for the task at hand such as lathes, buffing wheels, hand tools, heating chambers.

Cameron Weiss at work on a Unitas 6497

Which techniques are the most time consuming?

Hand finishing of the cases, and the movement bridges is the most time consuming.

Is there a technique that makes the best case for a watchmaker performing haute horlogerie? Or is it more so how well the techniques are performed?

Fine surface finishing of all components is what is most important.  Utilizing many different finishing methods for different surfaces and components is what allows for the designation of high watchmaking.

We picture you sitting at your watchmaker’s table putting Geneva stripes on countless 3/4 plates all day long. First of all, is this accurate? Second, how do you keep from getting complacent performing the same finishing techniques over and over?  

That is accurate, although there are also many more tasks for finishing and assembly of a finished timepiece. Sometimes the work can seem redundant at times, but when a timepiece is completed it is a perfect reminder of just how important each finishing step is to the overall beauty of the Field Watch.

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