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Shellac


Tmuir

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I'm currently servicing a Paketa 2609.

I thought it was going to be a simple strip down and clean, but on removing the anchor I discovered one of the pallets is not being held by the Shellac and has moved.

I'm going to have to hurry up and make my pallet warmer project sooner than I was planning on now.

 

My question is, is there any difference between the stick of clear shellac they sell at Cousins for watches and the shellac flakes you can get at artist stores?

Is watchmakers shellac more refined?

Basically do I need to order the shellac from Cousins, or can I just go to my local artist supply shop and use the shellac they sell?

 

Thanks

Tony

 

pallet.jpg

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I'm hoping if I set the stone back with a similar gap to the one still held in place it will be correct, but knowing my luck it probably wont be, but then I can atleast set it up on my microscope and see if I need to move it in or out, and go from there....

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I don't know if you have it but the Donald de Carle book, Practical Watch Repairing, has a good section on the banking and locking (setting the correct depth) of the pallet stones.

Cheers,

Vic

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52 minutes ago, Douglas1701 said:

Why do watchmakers still use shellac and not some of the good glues that are available now days?   Just a curious...newbee..

It's supposedly because glues can be unstable and release fumes over the years that can damage the dial (and maybe other parts of the movement?)

But I've also wondered if there's no better modern option... shellac is not that easy to use with the heating required. We have modern synthetic oils and no longer use whale oils, but still use the same glue as they did a hundred years ago.

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1 hour ago, Douglas1701 said:

Why do watchmakers still use shellac and not some of the good glues that are available now days?   Just a curious...newbee..

Often repairs are made with the next watchmaker in mind.  Shellac is a bit of a standard- if we used glue then we would have to standardize which glue to use otherwise the next watchmaker down the road wouldn't know which solvent or acid to use to remove the glue from the previous watchmaker's botched job. 

Shellac is fairly easy to use once you have a bit of experience.  It's not too difficult to remove if something goes wrong as well.

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To try to answer your question, the Shellac flakes you can get are probably the only substance that the watchmaker / repairer had available back when most of my older watches were put together, they are slightly more refined than the raw lumps of shellac that are available. They would still work now. There are more refined versions available of course that would do the same job now and arguably a more pure version may have different properties, but it would not be in the really old watches.

It is the same stuff that is dissolved into alcohol to use to put a fine finish onto wood and that tells you something about what you have to be careful about when cleaning watch parts, the pallet is treated differently.

Hope this goes some way to answering your question.

Cheers,
Vic

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In my time I had a tiny draw full of shellac flakes so never needed to buy any, it is surprising how little you will need. I never used a pallet warmer ether. Just make sure the stone is set as far in as it can go and hold pallets in an old pair of tweezers and  run it through the spirit lamp flame, do this until the shellac flake melts then leave to cool. The tricky bit is making sure the stone is correct in the first place. With modern pallets where the stone fits it is very snug to start with and shouldn't really move.     

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I have had great luck with the standard flake type shellac that can be purchased from a woodworking supply. Instead of a flame I use a tool called a plastic welding gun. The temperature can be adjusted on the gun which helps avoid burning the shellac.

Chicago Electric Welding 96712 Plastic Welding Kit with Air Motor and Temperature Adjustment

This also works great on a wax chuck.

david

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Shellac has many advantages over other types of fastening products. One big advantage is it can be drawn into thin hair size strands that are stiff enough to control. Watch parts are very small and a thin strand of shellac can be precisely deposited on the desired spot. A drop of glue on a watch part could  cover the part in areas where the glue was not needed or wanted. Another advantage is, once the shellac cools an extremely small amount of it will permanently hold the stone in place.  When you wish to remove the stone you only have to reheat it. Since alcohol dissolves shellac old shellac can be easily cleaned off before replacing another stone.

david

Edited by david
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Visited a local art shop today and they only sold very large bags of Shellac for quite a high price.

I think it would of been enough for everyone on this forum for their entire life and probably their children too.

I know a couple of people that used to do oil painting so I will go see them and failing that just order from Cousins.

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Have you tried the Bay, The UK Bay has them for £3.00 free postage and I went onto the Australian site and they were $3.17 Aus with about $3.00 Aus postage from the uk.  I don't know how that equates with Cousins postal charges to Perth however.

http://www.ebay.com.au/itm/10g-SHELLAC-jewels-watch-pallet-stones-roller-jewel-watchmakers-repairs-cement-/191446862073?hash=item2c931f48f9:g:I4gAAOSwaNBUixqR

 

Cheers,

Vic

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Then the modern art supply shellac will work just fine. I have a small bag basically a lifetime supply compliments of belonging to a local watch repair group. One of the members purchased the art supply shellac and supplied everyone in the group with the excessive so unfortunately the art supply store is not supplying for watchmakers.

Then it's been mentioned above the reason why shellac is popular especially on pallet forks is you conceivably may have to push the stone in and out a couple of times and to get it right. So the shellac can be heated up multiple of times without a problem. It's also nice in that it doesn't come off in the cleaning baths unlike some modern glues.

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I have looked at alternatives many times but without doubt Shellac is the best. UV glue is probably the next best thing BUT only if what is being adhered is in the correct position & you don,t want to re- position or undo in the future.

The old and tested ways are normally the way to go with horology. 

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