# Repair of a vintage Tissot pocket watch



## Guest (Dec 2, 2016)

This nice Tissot pocket watch arrived for servicing and repair. It looks good from the initial exterior inspection, but when I opened the caseback I noted that the mainspring arbour and the crown wheel were both missing.










*Fabricating a new crown wheel*

First task was to make a new crown wheel. First I sliced off a piece of EN8 carbon steel rod to serve as my wheel blank.










To face off the blank I mounted it on a brass wax chuck










Next I drilled the center hole and mounted it in a mandrel so that I could cut the teeth. It was secured with shellac.










Cutting the new teeth.










With the teeth all cut, I need to make a stepped section on the hole so that the shoulder screw can bottom out but allow the wheel to rotate without the right amount of side and end shakes.










The original winding wheel has a brushed finish so I do the same on my crown wheel, then install it and see how they match up.










*Missing mainspring winding arbour.*

Selecting a piece of EN8 high carbon steel bar, I install it in the lathe and get started on the fabrication. With the start of the square section cut out, I place the filling rest in position so that I can cut the square which will mate with the winding wheel.










After a bit of work with a file and arkansas stone, the square is coming along.










A quick test fit of the winding wheel to see how well it mates.










More cutting with the hand graver and it's starting to take shape.










Just for size reference, these are all the various dimensions - note the measurements are in millimeters










Happy with my progress, I part the arbour off from the rod and carry out some polishing and refinishing of the details.



















For strength and durability the arbour must be hardened and tempered, here it is after hardening, that is water you see around it










And next it is tempered to a blue before final polish










Test fitting in the barrel and mainplate and barrel bridge




























One of the pallet stones was chipped and needed replacing.










The pallet was heated to soften the shellac holding the stones in place and allow it's removal, a new stone was installed.










A new stone requires careful precise fitment so that the escapement works properly.










End results, a fixed watch brought back to life.










Thanks for reading.


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## dobra (Aug 20, 2009)

A lot of precision work, but brought a quality watch back to life. Very instructive, thanks.

mike


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## gimli (Mar 24, 2016)

I now have a much lower self-esteem.


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## Karrusel (Aug 13, 2016)

Horlogerie said:


> This nice Tissot pocket watch arrived for servicing and repair. It looks good from the initial exterior inspection, but when I opened the caseback I noted that the mainspring arbour and the crown wheel were both missing.
> 
> 
> 
> ...


 I'm pleased to see you've included references like shellac coating in your post. :thumbsup:

Never really understood why folk 'balk' at watchmakers charges, I suspect it's because they don't have a full understanding of their training, experience, costs and skill!

People will readily part with exorbitant amounts of money to solicitors, estate agents, garages, etc, in some instances for very little work?

In part, the trade (profession) can thank that great Danishman Bahn Bonnikson, for the formation of The British Watch & Clockmakers Guild.

In doing so, he elevated the trade to be recognised & equal to other eminent fields, such as medicine, science & engineering!

Thank you for an interesting post.

Alan


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## vek (Oct 27, 2011)

:notworthy:


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## davidcxn (Nov 4, 2010)

Fascinating post with great pictures & another vintage watch that has been given a new lease of life thanks to your skill. :notworthy:


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## andyclient (Aug 1, 2009)

Very impressive work , thanks for sharing


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## martinzx (Aug 29, 2010)

What a great post, thanks for sharing! Please continue to share it is much appreciated!

Cheers Martin :yes:


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## PC-Magician (Apr 29, 2013)

Proper watchmaking,its an art form.


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## Noslho (Nov 13, 2016)

Amazing craftsmanship! Thanks for educating us mere mortals.


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## Guest (Dec 5, 2016)

Thank you for the positive feedback.

On a trial basis I will post similar articles each week over the next month or so. Doing up a post takes quite a lot of time, especially taking and editing macro photo's, the time spent on creating a post is time away from the watchmakers bench, so the results of my postings will decide if my efforts are worth it. Only so many hours in a day and I have to make a living like everyone else.


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## harryblakes7 (Oct 1, 2010)

Excellent work, thank you for taking the time to do the pictures

Can i ask what type of wheel cutter you use? Is it computer controlled for the teeth, say for example 60 teeth, or do you use a round metal disc with the holes in?

I already have one lathe but may get another as i would like to get into gear cutting......


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## Guest (Dec 6, 2016)

Thank you.

I do not use dividing plates, they are prone to errors, limited by the number of holes they have and a general pain in the butt.

I made/assembled an electrical/mechanical dividing system where I use a stepper motor and a 90-1 wheel and worm assembly attached to the headstock, and for controlling I have the stepper motor connected to a Division Master, which allows infinite dividing possibilities, for example you can cut 1-9999 teeth or any value in between with a simple keyboard entry. It is accurate to 2/100 of a second (if I remember correctly) and doesn't make errors which ruin your work.

In my opinion, electrical dividing with a stepper motor is the only way to go.


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## PC-Magician (Apr 29, 2013)

Horlogerie said:


> Thank you.
> 
> I do not use dividing plates, they are prone to errors, limited by the number of holes they have and a general pain in the butt.
> 
> ...


 That is impressive.

As regards your posts I enjoy them very much so keep them coming when time allows.


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## chocko (Nov 9, 2008)

Just came across this post, amazing photo details and very informative.Thanks for sharing. :thumbsup:


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## harryblakes7 (Oct 1, 2010)

Thank you for the advice "Horologie" will look into it, i hope to build a small workshop when i have done fitting a kitchen........

Something i need to make is a winding pinion for a chronograph pocket watch, at the end of the winding stem is a crown wheel with a bevel gear, it also slides for the activation of the chronograph, it gives me a headache looking at it....... :laugh: Will do some pictures when i come across it, rattrapante as well.......


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## tixntox (Jul 17, 2009)

Never mind the skills, I wish that I still had the eyes and hands to do that sort of work. Well done sir. I salute you. :notworthy:

Mike


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## Roger the Dodger (Oct 5, 2009)

Thanks for posting....much appreciated! :thumbs_up:


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