Watch hands fiber laser test

Another test of the fiber laser. This time with watch hands.



Found a nice sward hand graphic. Not to any particular scale. Got a box of cheap double sided blades.

Beam width looks good. The hands though will not separate from the rest of the metal. At this thinness the metal acts like a spring.

Increasing the power only heats the metal up, which warps it. The laser is only 30 watts. The giggle AI says that effectively the laser is drilling a chain of holes in the metal. Why a frequency of 30 cuts better than a higher frequency.

When attempting to separate out the hand, the metal does not break at the line like it does on the thicker blades. It looks more like it simply tempered the line to blue. Fatigue fractures do not stop a the line.

There are suggestions to use cleaning passes, with lower power, which in theory removes some of the carbon scoring.

I just looked up the video again. Had to use 'chess clock' in the search terms.


I see they say low power for 600 passes. I find that more than 5 passes and the metal turns blue and warps. The best results were from 3300 mm/s 42 power and 30 freq. More than 5 passes with gaps of time and the metal warps.

I think traditionally watch hand replacements were made from broken mainspring steel. Might try that next.

I did try turning the freq to 60 and another 5 passes which makes the thing look nice.

Missed the point where they sanded the part before trying to break it free. Pre sanding may also help clean the finger oils, which tend to mark the metal more than the cleaner parts. Or rough up the reflection.

You tube also suggested a more recent video


which is a bit longer. I probably should have watched it first. I found the part where they were doing the same thing I was. I also see they were doing some things I was considering when driving home, like extra lines to wear down the side of the cut. I also see they are using the same program and can see what settings they use.

Does go to show, that if one thinks of something. Many others are thinking the same thing. Which is why intellectual property ideas are so stupid.

There is a whole lot more stuff in the suggestions since I last looked for watchmaking with lasers. Curious that these videos showed up this morning on this computer, and not last night when I was searching for the speed power frequency setting.

Just goes to show that the videos are not for actual instruction. They are there to get you to click, then go to the next one as the voice over is so annoying. I tend to mute and use the auto generated captions more often than not.

This week's update.

I tried the setting from the video. Much the same result. The metal only etches so much then turns blue and warps.



A bit better this time, but the hub shattered when I tried removing it. Might have the fill line a bit wide. The edges still are not breaking clean like they do with brass.

The lowest settings do not even mark the material.

Most of the vids indicate 40 to 90 passes or more. I find the warping happens around pass 5 or 6. Then the focus gets lost.

I am using cheap razor blade steel. Forgot to look for some scrap mainspring to try. I did get some respectable results with single edge razor and old Xacto blades when I was playing with the date set levers.

Time consuming. I spent three hours with this session.

If it is Tuesday must be pipe organ day...

Followed by a trip to the Makerspace on the way home. The bridge toll is now 8.50 USD for a 7 mile drive. So stopping on the way home after crossing the bridge an negligible gas usage since it is on the way make sense.

So we now have some Tuna Can watchmaking. Which is actually unlike other posts today not a joke.

Attempting to cut a sweep hand from a scrap of mainspring has the same warping issues that the razor blades presented.

I had cut some dial blanks from a shortbread biscuit tin. I sabe tuna cans for small parts assortments. So was noticing they are made from really thin steel that can be cut through with an xacto knife or punch. Modern cans are really thin. I think they are still tin plated and have some sort of coating on them.

So this time some success. I now have a set of hands.


I did attempt cutting another dial blank, but it was getting late and missed on the focus so the date window is more melted than cut and the size is off.

The metal is quite soft, so it is easy to deform the hand. Which might not be a bad thing .

Results are a bit crude compared to professionally made hands. They do look like hands.


Will be interesting to see what they look like after polishing. If they will take some paint an lume.

Could be some of the problem with warping relates to the material being too small. I did the minute hand twice. The first time I overlapped material removed next to the seconds hand. The one side warped. I also attempted to do this in one session. The tin can material will cut through with 2 to 10 passes. I left the fill on 95 passes the first time and cut the sweep hand. With the minute hand part too close to the edge the one side warped, the lume slot also did not cut through.

The second attempt at the minute hand was better although the sides got bent out of shape a bit. Probably should set for a narrower lume slot.

Progress continues ...