My 1967 Longines Ultra-Chron is running a bit slow and I was wondering if I could regulate to better performance myself. It's running -30 sec per day according to iPhone Timegrapher app.
It used to run pretty much +/- 2 sec per day but one day it started to run 5 minutes faster and took it to service. They managed to get it down to -30 sec now, but I'm not happy

How do you regulate it?
I could take it to a watchmaker, but I'd like to learn to do this myself.

 

Sounds like a good old game of chasing seconds for you my friend until you find out how to......

I would be making friends with your new watchmaker if the last one couldn't do better than -30 on a Longines Ultra Chron

 

In my experience, you need to make a small adjustment to the regulator, check how much that changes the beat rate, and then proceed iteratively, until you get reasonably close.

 

Using the regulator to rectify timing problems is the last place you should be trying.

Get a competent watchmaker to investigate, starting from the mainspring/barrel and looking at the whole movement, not just the regulator.

 

When was the last service?
Some dirt or dry oil would have a great impact on the time keeping

 

Maybe I mis-read the OP, but it seemed to me that the watch had just returned from a service.

 

The previous service was in 2014. It was made by the previous owner.
When I got the watch it was running very well. But I guess it got a nudge or something, because one day out of the blue it started running very fast.
So I took a local watchmaker. They said they can fix it. Just for information, they don't work on vintage swiss watches normally or rarely (ex-USSR country Estonia is, so they don't have an experience).
I would never take my Speedmaster to them There's Omega AD in another city, but they also think I'm crazy to expect old watch running better. That's how it is here.
But seemed like an easy fix.
It was not a service really, I don't know what did they do.

Now it runs a bit slow.
I could take it to them, but I know what they would be saying: it's 50 years old watch, what are you expecting...
That's why I'm thinking perhaps little tinkering could make it better.

I'm selling this watch in eBay currently for a pretty low price, so sending it to pro watchmaker abroad would not make a sense.

 

With a timegrapher and by turning the micrometer adjustment screw you will be able to asjust in the 2 most common position dial up and crown down

 

Are you talking about that screw in the middle of the red circle? I do have some very small screwdrivers, but none of them work for this one. I guess I need to take it to a watchmaker after all.

Btw, how does it happen that watch works 0 sec/day one day and 5+ min/hr next?
What did the watchmaker do to fix that?
I've heard that magnetism could make the watch run faster, but when I tested it with a compass, it showed very very slight magnetism.

 

There's no point in trying to regulate that. The balance amplitudes are quite low, the beat error is huge - to me these indicate that the watch has not been properly serviced or is in need of servicing, so trying to regulate it will be a rather fruitless exercise.

Cheers, Al

 

Thanks to all!
Yeas, the amplitude is quite low indeed.
Before that one day, the watch worked perfectly fine, then started running super fast ahead.
So, I am not sure it's really a service question because it ran like 1 year within COSC ratings.
I cannot really have it properly serviced locally, no one is up for that.