Copper, Heat & Small Victories

I've been spending some time experimenting with a copper dial for an ETA 6498 small-seconds movement. This is my first attempt working with copper, and it's proving to be an interesting material. It engraves beautifully with the fiber laser, but it's also incredibly soft and picks up surface textures very easily.

After scrubbing the dial clean, I popped it in a convection oven to dry. I noticed the copper beginning to darken. Rather than pull it out, I decided to see where it would go. The surface gradually developed a range of warm reds, yellows, and oranges, I pulled it out when it reached what my son called the sunset stage. Interestingly, areas where I'd attempted a sunburst finish with steel wool took on a more yellow, golden appearance. Clearly, there's more to explore with surface preparation and heat-induced coloration.

There are still some mechanical issues to work through. The small-seconds subdial needs to be engraved a little deeper and opened up slightly to provide adequate clearance for the hand.

Speaking of hands, I've also been experimenting with making my own hands, and for the first time managed to produce a set that actually fit and could be installed on the movement. They're too thick at present and interfere with the small-seconds hand, so the next iteration will need a slimmer profile.

Perhaps the most satisfying achievement was successfully using a staking set to reduce an oversized hand hole until it provided a proper friction fit. It's a small detail, but making a hand that can actually be fitted to a movement felt like a meaningful step forward.

On the movement side, I also experimented with laser annealing the bridge for the first time, adding a Pine Street signature. This is a Seagull ST3621. I only have one ETA 6498 movement at the moment so I will save that until prototyping is finished :)

After some testing, I've established laser settings that produce a result I'm pleased with.

A little metallurgy, a little machining, a few clearance problems, and several new skills to build on.