Regulating with the Delgetti-key

[Delgetti]

I’m working on mechanical wrist-watches for two years now and in this time I came very often to one problem concerning watches with a regulator arm. I wanted a watch to run a little bit slower or faster (let’s say 3 seconds), so I had to push the regulator arm a very little distance. On many of my watches these arms have quite a big breakaway torque, so when I increased force and the arm started moving, it jumped a bigger distance than I wanted it to do (of course this led to a timing “correction” of 20 seconds, not the 3 seconds I wanted). Not my idea of regulating, this is just “try and try again, good luck”. Searching some forums on the internet for a tool to do this better I didn’t find a solution for me.

So I had a close look at the regulator arms of my watches, did some measurements and finally built this little tool. The tool head grips over the regulator arm while the watch is on the timegrapher and due to the tools long lever arm (which is about 4 inches) I can manipulate the regulator position very precise. Here are some pics of my work on a Rolex 5513 with 1520 movement. The watch ran constantly +4 seconds per day and I wanted to slow it down to +1 second. No problem with the Delgetti-key.

 

 

 

 

 

[matabog]

Not a bad idea!

Did you manage to shave only 3 sec at a time?

[Delgetti]

@matabog: Sorry, my english is not that good, I don't understand the question. What do you mean?

[matabog]

Was the tool good enough to regulate the watch to make a correction of only 3 seconds?

[Delgetti]

Ah, okay, got it.

As you can see from the last pic: While the tool head grips over the regulator arm I don't hold the tool in my hand but put it on a book. Then I push the end of the tool in the needed direction millimetre by millimetre. Because of the tools long arm the effect on the regulator is a fraction of a millimetre. I could observe the value on the timegrapher turning down second by second. So in this special case with the 5513 a regulation in steps of a second was possible.

[matabog]

I understood the principle. I was not sure if the regulator was moving indeed so little - there is a sort of elasticiy of the regulator arm and a "friction breaking force" and when it starts to move, it moves too much.

But it seams to be working, so I will give it a try!