Removing Hands Of Fusee Watch ?

[cdjswiss]

I am working on my first fusee lever watch. Here is a photo of the hands. The square nut is used for setting in the clockwise direction with the appropriate key, and I assume that to remove the minute hand the nut must be unscrewed anticlockwise using the same key. It is extraordinarily tight for such a small nut and before applying more force I should be pleased if someone can confirm that it should be unscrewed.

 

 

[bobm12]

Wow, Colin, completely out of my league! :) I'll be curious too about the solution!

 

Cheers,

 

Bob

[Geo]

Colin, I think you will find it's a taper fit on the pin and the square remains permanently attached to the hand.

Edit. Rafal is correct, I have checked out an old movement. See my next post.

[Rafal]

looks like English style hands, seems to be mounted the same way as normal hands except hour hand has square hole, try gently pry with your hands levers/remover to see if thats the case.

[Geo]

I've just checked, and pulled one from a movement I had lying around.

The hand has a square hole in the middle. Pull it off the square, them pull off the hour hand. That leaves what looks like a canon pinion with a square. Remove the dial, and the hour wheel will slide over the pinion and square. You will now be able to pull off the pinion with the square. It is fitted on a taper, and requires a good pull or a bit of leverage.

Here's a photo to help.

[cdjswiss]

Many thanks gentlemen for the correct information. Here is the result.

 

 

 

It was sold as a non-runner. After cleaning the balance it was running well for 36 hours on one wind but only the second hand moved. So the next step is to tighten the cannon pinion. Thanks George for the illustration of that step. A couple of taper pins only and I shall have the dial off, but that will await the morning as it is now time to sample a bottle of Cahors.

[cdjswiss]

Yes, very fine 2010 vintage.

 

If the cannon pinion is slipping it should come off easily?  But I do fear that the problem may be more serious. However, as the second hand turns it cannot be too severe. Perhaps a broken cannon pinion?

[Geo]

Colin, it is not a canon pinion as you used to. The pinion has has a precision taper and don't compress it as you would a modern canon pinion. When fitted this pinion is not meant to slip at all.

To tighten the setting operation of the hands, you have to remove the whole shaft that goes through the centre wheel. You will have to put a slight bend in the middle of of this so that it increases the friction fit inside the tube of the centre wheel.

To re-fit the geared pinion with the internal taper, you have to support the other end of the shaft that you have just bent slightly, and tap the pinion onto it with a ounce and very lightweight hammer. It is the same as fitting a morse taper. Once you have that reassembled, fit the minute and hour wheel then the dial and hands. The hands will press on fairly easily.

There is a possibility someone has been working on the watch before that didn't know how the system works. The first time I came across it and saw a bent shaft I thought there was a problem and straightened it. Guess what, the hands were so slack the movement wouldn't drive them and they turned like propellers when I tried to set the time!

[cdjswiss]

I couldn't wait. Here the cannon pinion came away easily and a 0.9mm watch hand fitted to the centre arbor appears to be keeping good time. There was some goo under the minute wheel that would explain why setting the hands sometimes met a sticky spot but was mostly too free. It remains to tighten the cannon pinion using the Bergeon chisel tool in my jeweling press.

 

[Geo]

It remains to tighten the cannon pinion using the Bergeon chisel tool in my jeweling press.

DON'T DO THIS Colin!

The pinion has to be rock solid on the shaft, if you use your canon pinion tool on it you will ruin the internal taper. The pin must be removed and bent slightly where I have indicated to get the correct friction.

There is usually a small shim washer on the other end of the shaft to give the correct end shake.

[clockwatcher]

Wow, a cliff-hanger!

[cdjswiss]

Thanks George. Your illustration is of what Fried calls the clock type of centre pin system where the cannon pinion is firmly fitted to the pin. Here is a photo of my cannon pinion and I see a dimple. My watch presumably has the click-on cannon pinion?

 

 

I now realise that I cannot use the Bergeon chisel tool. I must indent the dimple further with a staking set punch and a short pin fitted inside the blind canon pinion to control the dimpling.

 

Comments and advice before I start to hammer?

[cdjswiss]

Or has a tinkerer made the dimple in what should be a press-on cannon pinion ?

[cdjswiss]

The centre arbor has a slight taper from 0.96mm at the base to 0.93mm at the tip. But there is also evidence of the use of a click-on cannon pinion. When I hold the arbor firmly in a pin vice it doesn't turn. All of this suggests a dimpled click-on cannon pinion system. The watch is dated 1900.

 

 

[Geo]

The watch that I pulled the pinion off of yesterday pre-dates 1900 and has the the same dimple ground out of the side. The trench watch that I worked on a while ago was from 1913 and has the type of bent pin system that I'm talking about, hence my concern about you damaging your watch.

http://www.watchrepairtalk.com/topic/1520-trench-watch-help/?hl=%2Btrench+%2Bwatch

Having said all of the above, if as you say you cannot turn the pin using a pin vice it suggests otherwise. Is it possible to have a look at the lower end of the centre wheel to see if it has a small pivot, or a through going pivot with the pin that I describe, just to make sure?

[cdjswiss]

Having said all of the above, if as you say you cannot turn the pin using a pin vice it suggests otherwise. Is it possible to have a look at the lower end of the centre wheel to see if it has a small pivot, or a through going pivot with the pin that I describe, just to make sure?

 

Good sleuthing George - It has a small pivot. Case closed. I shall dimple.

[Geo]

Excellent Colin! All's well that ends well.

[oldhippy]

I'm a bit late on this one. It just pulls off just like any cannon pinion.

[cdjswiss]

I'm a bit late on this one. It just pulls off just like any cannon pinion.

 

Beware of the cannon pinions that should not be pulled off.

I quote Fried:

"Therefore removal of this type of canon pinion (hollow pinion type) should not be attempted in the same manner as the snap-on type as this might result in 'springing' the main plate".

This was the concern that Geo was voicing.

[oldhippy]

Beware of the cannon pinions that should not be pulled off.

I quote Fried:

"Therefore removal of this type of canon pinion (hollow pinion type) should not be attempted in the same manner as the snap-on type as this might result in 'springing' the main plate".

This was the concern that Geo was voicing.

Thanks for the advice. I've been retired now for many years and I have about 30 years under my belt as a watch/clockmaker.

 

Happy Christmas

[cdjswiss]

For the record:

The cannon pinion of my fusee watch has the ground-out notch with a very small dimple in the centre. When I punched the dimple to my surprise a separate plug about 0.5mm diameter, that you may just be able to discern withing the pink circle, was driven into the pinion up to the brass pin that I had slipped inside. This plug could be seen under the microscope within the pinion projecting about 0.03mm. It was all that it needed to give the cannon pinion the tight, but not too tight, fit onto the centre wheel arbor. The minute dimple is put there simply to centre the punch. They certainly knew how to build watches in those days. It is now running perfectly.

 

[Geo]

Great result Colin, another one to file away in the memory banks. That's one that I haven' seen before.