*GASP* My 1953 Oyster gains 5 seconds a day.

[Aramis9]

well... lets get this in perspective, it beats at 18,000 BPH, so in effect its one beat per hour fast, that's 1/18,000 inaccurate.

As an amateur tinkerer, self taught for years on old watches bought for little money I'd like to add my dollars worth, mainly regarding the regulation or time keeping of mechanical watches. It's common to find posts from watch owners either bemoaning the accuracy of their piece or wishing to regulate it themselves.

Some of the technical terms I use might be incorrect so I apologize for that in advance and expect to be corrected.

When looking at a purchase of an old watch the first thing I do on opening the back, or looking at any picture is check that the index is bang in the middle of the scale on the balance cock. This is a good sign that the movement could be running as the maker intended. You will see some that are banked over to extremes to compensate for a fault somewhere else.

It can be a weak mainspring(watch will rate fast), an incorrect stronger mainspring(watch will run slow),worn or badly lubricated works,or a truly bodged job on the balance or hairspring... leave the watch where it is and don't buy it unless you are willing to pay out on a repair. With experience you can listen for worn balance pivots by listening to the beat dial up and then dial down, if there is a difference in the sound(not the loudness) the balance pivots could be worn, causing the pallet to miss- hit the ruby jewel(dial down) or even miss the jewel altogether on an extremely worn balance when dial up.

Anyway.. back to attempting to regulate a movement yourself..

A typical scenario.. Hero decides to have a go at regulating his pride and joy, reads up a bit and watches a few you tube vids. He manages to get the case back open, in the process he allows debris from the joint to drop into the movement. Armed with a toothpick he now shoves the regulating tail in the direction he believes will alter the rate. The amount of movement needed is tiny, the hairspring is kept to length by normally two parallel pins. Unfortunately these pins due to a previous bodge are not moving in the same radius as the outer run of the hairspring, so they lose contact with the hairspring, which now 'bounces' between the pins.. result.. the watch will run VERY slow. Hero now, after 24 hours of wondering why it went slower instead of faster jams the index even further over, causing a tiny splinter to detach from his toothpick which drops onto the hairspring. The pins now make decent contact with the hairspring, the watch due to interference with the splinter of wood effectively shortening the hairspring now gains 10 minutes and hour. Frustrated, and breathing heavily into the movement he returns the index to the middle of the scale, puts the back on and takes it to his nearest watchmaker. Who duly charges him for a clean and regulation.

I've seen all sorts of fixes on regulators and hairsprings, most of which needed a new complete balance to fix. Index pins forced together to grip the hairspring, index pins snapped off, then the hairspring distorted so its resting 'hard' against the remaining pin, super glue keeping the hairspring to the pins, incorrect regulator bodged on which will not move. Balances with material removed or added in mind boggling methods.

A professional watchmaker is usually a proud artisan, treat him with respect. He will inwardly sigh when confronted with some one else's work but then fix it. Please don't try to regulate your own precious marvel of micro engineering.

I used to spend hours regulating a cut compensated bi-metallic balance with a breguet hairspring without access to a timing machine, it was fascinating stuff, but education costs so pay your watchmaker for the service he is trained and experienced in.

Regards.. Martin.

[tickious]

The hairspring should bounce evenly between the regulating pins. Still sound advice. If in doubt, keep out.

[Aramis9]

Originally Posted by tickious

The hairspring should bounce evenly between the regulating pins. Still sound advice. If in doubt, keep out.

If I understand your meaning I have to disagree, the pins are there to effectively keep the hairspring at the optimum length to maintain the correct rate.
They need to keep the hairspring at a constant length, if the spring bounces between the pins it is shortened then lengthened then shortened again with every cycle of the beat. Maybe you mean the 'breathing effect' that can be seen on a spring that is working well on a balance with good amplitude and poise?.

Regards.. Martin.

[tickious]

If the pins are touching the spring you wouldn't be able to regulate it as the spring would be pinched. It's a level of degree. Also the gap between the pins affects the time keeping. One adjustment doesn't fit all.

[dysondiver]

own a screwdriver with a blade of aprox half an inch or so.
only ever turn screws that the blade fits perfectly ..
or nuts that can be tightened with a 12 inch shifting spanner .
..
.
.
.
. anything else leave it into a trained watchmaker .... and i dont mean the guy in the mall that changes batteries ,,, just my thoughts
and welcome to the forum , i feel the force is not yet strong in this one
wax on ..... wax off ,,,

[tickious]

Originally Posted by dysondiver

own a screwdriver with a blade of aprox half an inch or so.
only ever turn screws that the blade fits perfectly ..
or nuts that can be tightened with a 12 inch shifting spanner .
..
.
.
.
. anything else leave it into a trained watchmaker .... and i dont mean the guy in the mall that changes batteries ,,, just my thoughts
and welcome to the forum , i feel the force is not yet strong in this one
wax on ..... wax off ,,,