Making a new movement clamp on an Omega 344 Bumper with basic tools and materials

PastorChris · February 1, 2021

I want sure if this should be in Walkthroughs or Achievements but here it is.

The back story: I picked up a 1952 Omega Seamaster on Ebay a few years ago. Not the original dial but very pretty to my eye and it reminded me of my grandfather's Omega, which was sadly pilfered by an estate buyer/estimator after this passing. That is another fairly long story.

The watch had a habit of fogging a bit in warm weather when I was perspiring. I took it to our local jeweler (excellent) who gave it to one of their watch makers (not the greatest). They fixed the problem simply by CRANKING down the case back, rather than putting in the missing seal. It worked, but I was less than happy with the job when I opened it up a few days ago.

I opened it because it felt like the movement was a bit loose because of a rattle that did not correspond with the familiar "bump" of the bumper wind movement.

I made some measurements and ordered a few different seals from Esslinger. The movement clamp was a little lose and it kind of looked cobbled together or adapted from something else since the end that went under the edge of the case looked like it had been shortened with and end nipper and not dressed with a file afterwards. It was also not holding the movement especially well when I tightened the slightly loose screw.

I decided that I could cobble something at least as well with materials on hand and tools I had or could make, so here is my effort. Please don't cringe too much.

Here is where I started, in the workshop with the screw and the broken clamp set in a piece of rodico. The first task was to get a hole of the correct size in a piece of suitable material, which I decided would be some sheet nickel-silver (German Silver) without having any tiny little drill bits.

Also photos of the movement with the clamp removed positioned at about the 12 o'clock position, the clamp itself, and the screw.

PastorChris · February 1, 2021

Next was to the materials and tools. I decided upon some sheet nickel silver, which I had on hand. I knew it would be easy to work and manipulate and be reasonably durable. This is an alloy of copper, zinc, and tin. Like similar metals, if you heat it to red hot and then quench rapidly in water, it gets very soft and easy to bend without breaking.

I do not have tiny drills, and there is a good hobby shop about 15 minutes away, but I figured I could get around that.

I cut a strip of the material and then flattened with with a brass hammer on my bench vise. I used a typical center punch to mark where I wanted the hole. I then use d apiece of Kydex, which is a thermoplastic, as an anvil and struck the location again.

The index is firm, but also slightly flexible, so I knew the center punch would make a goodcdimple on the reverse side of the nickel silver.

I then tuned the material over and filed down the dimple. After a repetition or two there was a tiny hole in the strip of nickel silver.

Next I needed a broach to enlarge the hole. I do a bit of canvas and leather sewing for my own purposed and have a good supply of old carbon steel triangular sail making needles from England. Domestic ones might suit the purpose too, but I cannot guarantee the results LOL.

It was a simple matter of grinding down the flats of the needles on a belt grinder with a worn 220 grit belt, going slowly to preserve the harness of the needles, until the corners met and were sharp.

The home-brew broach was then used to enlarge the tiny hole until it fit the screw.

Edited February 1, 2021 by PastorChris

PastorChris · February 1, 2021

Now it was time to fit the shape of the new clamp to the movement and then bend it so it would perform the intended function and then do the final fitting. You can see the range of colors that result form the heating and quenching in one of the photos.

Ever more careful and fine filing and continual testing against the movement until the tip of the clamp fit into the movement. Then simple bending and adjusting of length and trial fitting again until voila! A new clamp that holds nice and solid.

This was a fun bit of adaptation and using the know qualities and behaviors of the materials to accomplish the job.

This is a useful skill to have until I collect more tools and eventually containers of "donor movements" and collections of little screws and bits. But I currently have none of that. So there it all is.

I hope this inspires others to try making some things they do not have at hand. This was done with basic needles files and tools most people probably already have around.