Jewel and balance staf replacement.

[graemeW]

1 minute ago, Neverenoughwatches said:

Absolutely Graeme , everything is achievable given time, and that depends almost entirely on skill and knowledge...which Nev has a metric tonne of...which is why he makes it look easy. I do have a question G... how did you remove the old jewel ? I think you said you popped it out. 

Yes, pushed from the back with pegwood. Came out easy enough. I've raised the edge of the rubber over area too. If I could find the right jewel, I could poke it back in and rub the edge over again.

But the old jewel was quite thin and beveled top and bottom. The new one looks thicker and is square at the bottom. I'm not convinced it's going to fit!

I could manage a rubbed in jewel with what I own. Reaming the hole and press fitting a modern one requires tools and skills I don't have yet.

I am tempted to push the jewel out of another movement that will probably be scrap, but don't want to break it. 

[Neverenoughwatches]

Let me link you to Mark's video about replacing rubbed in jewels, in this case it was a top balance jewel.

https://www.watchrepairtalk.com/topic/7404-old-style-rubbed-in-jewels/?do=findComment&comment=156030

4 minutes ago, graemeW said:

Yes, pushed from the back with pegwood. Came out easy enough. I've raised the edge of the rubber over area too. If I could find the right jewel, I could poke it back in and rub the edge over again.

But the old jewel was quite thin and beveled top and bottom. The new one looks thicker and is square at the bottom. I'm not convinced it's going to fit!

I could manage a rubbed in jewel with what I own. Reaming the hole and press fitting a modern one requires tools and skills I don't have yet.

I am tempted to push the jewel out of another movement that will probably be scrap, but don't want to break it. 

Sounds like the new one is not shaped to be rubbed in, both sides should be domed for the rub to seat over smoothly. 

[graemeW]

8 minutes ago, Neverenoughwatches said:

Let me link you to Mark's video about replacing rubbed in jewels, in this case it was a top balance jewel.

https://www.watchrepairtalk.com/topic/7404-old-style-rubbed-in-jewels/?do=findComment&comment=156030

Thanks.

I watched that before. I'm reasonably happy I can fit the jewel, I'm less confident I'll get the right jewel.

I think the modern jewel will seat ok, but it doesn't have the bevel on the flat side to take the rubbed over metal. Also, if it's too thick, it will gold the cap jewel away from the main plate and effect the end float.

I suspect I might need to salvage a jewel from a scrap movement. 

[LittleWatchShop]

57 minutes ago, caseback said:

Not beeing deterred by the fact that you're specifically asking "experts" (which I'm definately not!), I would say it would depend on whether or not originality is an issue and what the impact on the value is..

That is why I qualified my proposal with "I own" because that can make a difference.  I have made this kind of call several times with respect to dials.  If it is my watch and I have no plans to sell it, I will make it look the way I want.  I had one instance where I was repairing a treasured watch for a friend of a friend and the dial was damaged.  I found a close replacement and gave the owner the option.  In the end, the original was kept though I did repair some of the markers.

[graemeW]

25 minutes ago, Neverenoughwatches said:

Let me link you to Mark's video about replacing rubbed in jewels, in this case it was a top balance jewel.

https://www.watchrepairtalk.com/topic/7404-old-style-rubbed-in-jewels/?do=findComment&comment=156030

Sounds like the new one is not shaped to be rubbed in, both sides should be domed for the rub to seat over smoothly. 

Exactly that

Found this video.

So the modern jewel can be ground. I guess that's an option if I can't salvage one.

 

[Neverenoughwatches]

Nice accurate way of burnishing back over. Expensive solution though unless you already own the lathe equipment.  I would ask Nev for some pointers on doing it by hand without the dedicated tools. There must be a stake for doing this in a staking or upright frame.

[graemeW]

7 minutes ago, Neverenoughwatches said:

Nice accurate way of burnishing back over. Expensive solution though unless you already own the lathe equipment.  I would ask Nev for some pointers on doing it by hand without the dedicated tools. There must be a stake for doing this in a staking or upright frame.

I have lathes, although larger than watchmakers. I also have a dremel, which is all he used in the video, and various pendant drills etc.

I don't even have a staking set yet, I only have basic hand tools. But, if I can't yet buy the tools I need, I can make them. 

The video grinding the jewel looks achievable to me. My main concern would be loosing it.

I'm ok working indoors, but drop a jewel in my workshop and it's gone forever.

 

Anyone got any idea what grit of diamond paste would be needed to grind the jewel?

Just had another realisation. I don't want a flat jewel do I? I want a convex one. The top curve holds the oil in the center between it and the cap jewel right?

Makes things even trickier as cousins only have 0.11x0.80 and 0.11x1.5

[Neverenoughwatches]

26 minutes ago, graemeW said:

. I also have a dremel, which is all he used in the video, and various pendant drills etc.

I missed that, i thought the dremmel was just used to polish the burnisher. Thats a decent rotary tool with no runout, I use a proxxon which is accurate. 

[graemeW]

If I tackle another watch first, so I'm sure I have a scrap main plate, I might be able to salvage the balance jewel from that. It seems to be identical. Failing that, another option that doesn't require me making a bush (I really want a watchmakers lathe!).

Ream hole out 1.49

 

Press a convex 0.11x1.50 jewel in

 

 

Seems a bit brutal though. Especially on what seems like quite a nice movement. It even has a bimetalic balance wheel, the only one of my 1917 watches with one.

1 minute ago, Neverenoughwatches said:

I missed that, i thought the dremmel was just used to polish the burnisher. Thats a decent rotary tool with no runout, I use a proxxon which is accurate. 

I was equally as amazed at the bearing quality in his dremel! 

[nevenbekriev]

OK, if it was me, I should use suitable jewel from useless bridge or cock or plate. Thus one can check how the pivot gets in the hole and know if it is  correct or not.  I have shown the simple way how to get the jewel out without breaking it. 0.1mm pivot size is much more realistic than 0.07

Yes, the old jewel was for sure rubbed in and placing press fit jewel on it's place by rubbing in is possible, but the new jewel has to be rounded - at least one of it's edges on which the rubbing closes. If the jewel is thick (high), it can be honed on diamond plate - the side with the internal cone - as the other side of the jewel to be on correct distance from the cap stone

[graemeW]

50 minutes ago, nevenbekriev said:

OK, if it was me, I should use suitable jewel from useless bridge or cock or plate. Thus one can check how the pivot gets in the hole and know if it is  correct or not.  I have shown the simple way how to get the jewel out without breaking it. 0.1mm pivot size is much more realistic than 0.07

Yes, the old jewel was for sure rubbed in and placing press fit jewel on it's place by rubbing in is possible, but the new jewel has to be rounded - at least one of it's edges on which the rubbing closes. If the jewel is thick (high), it can be honed on diamond plate - the side with the internal cone - as the other side of the jewel to be on correct distance from the cap stone

This is my prepared option by far.

Means I need to do the other watch first to make sure I have a spare jewel. I already checked the old staff in the donor watch's jewel and it's perfect.

Is there no safe way to get the jewel out without cutting the part up?

I pressed the broken one out with wood like you show. Can't quite decide if it felt like too much force for a good jewel to survive. If I have to cut it up though, I will.

Ive ordered the new staff (well, apparently, a pack of 12!)

Figured it's best I measure the actual staff I'm going to use before settling on what jewel to use.

I'll use the waiting time to try and sort the watch (2 movements to build 1) which will be the jewel donor.

[SwissSeiko]

This type of repair is exactly why I got my jeweling tailstock for my lathe. But if you dont have all the equipment, getting a donor movement with a good jewel is a great start. I have run into issues where the donor movement had a pivot hole that was smaller, ever though they were the same movement. Either it was a change at the factory, or a previous watchmaker made the change. So I believe it is best to wait for the replacement staffs, and measure those, then get a replacement jewel. Im lucky enough to have an assortment of jewels so Im not waiting on them in the mail, and you always have the slight chance that the jewel you order is not correct. As Nev said, you can change jewels dimensions relatively easily, if you have the tools. A diamond disc on a lap will shape the outside, and then a hardened steel rod with diamond paste can shape the inside. A watchmakers lathe is perfect for both of these tasks, so maybe its a good reason to buy one. You will have to make the hole polisher yourself, and put a slight backwards taper on it. It will need to be the exact dimension of the hole. You will also want jewel chucks to hold it, but you can get away with a super glue arbor type solution.

 

If you're wanting to maintain originality and use a rubbed in jewel instead of a friction jewel, you'll need the spreader/rubber tool, I cant think of their correct name. I use my lathe for this. If this is just a personal watch and you want a repair that works, I'd use a friction jewel.

Do you have a jewel press?

[graemeW]

12 minutes ago, SwissSeiko said:

This type of repair is exactly why I got my jeweling tailstock for my lathe. But if you dont have all the equipment, getting a donor movement with a good jewel is a great start. I have run into issues where the donor movement had a pivot hole that was smaller, ever though they were the same movement. Either it was a change at the factory, or a previous watchmaker made the change. So I believe it is best to wait for the replacement staffs, and measure those, then get a replacement jewel. Im lucky enough to have an assortment of jewels so Im not waiting on them in the mail, and you always have the slight chance that the jewel you order is not correct. As Nev said, you can change jewels dimensions relatively easily, if you have the tools. A diamond disc on a lap will shape the outside, and then a hardened steel rod with diamond paste can shape the inside. A watchmakers lathe is perfect for both of these tasks, so maybe its a good reason to buy one. You will have to make the hole polisher yourself, and put a slight backwards taper on it. It will need to be the exact dimension of the hole. You will also want jewel chucks to hold it, but you can get away with a super glue arbor type solution.

 

If you're wanting to maintain originality and use a rubbed in jewel instead of a friction jewel, you'll need the spreader/rubber tool, I cant think of their correct name. I use my lathe for this. If this is just a personal watch and you want a repair that works, I'd use a friction jewel.

Do you have a jewel press?

I don't have a jewel press, not yet.

I am probably going to sell one of my bigger lathes and put the money into a smaller one. I do like a lathe, so don't need much excuse.

I'll make any watch tooling I need in the short term while keeping an eye open for good quality proper stuff. 

[LittleWatchShop]

34 minutes ago, SwissSeiko said:

watchmakers lathe is perfect for both of these tasks,

I am trying to visualize your setup for this. I am awash in WW lathes, so maybe I could dedicate one to this task.

[Neverenoughwatches]

3 hours ago, graemeW said:

I was equally as amazed at the bearing quality in his dremel! 

A simple dc motor with a short spindle of say 5mm would be equally as stable at that length...perfect for grinding a jewel .

[SwissSeiko]

29 minutes ago, LittleWatchShop said:

I am trying to visualize your setup for this. I am awash in WW lathes, so maybe I could dedicate one to this task.

You would mount the diamond disc(an actual lapping disc, not a diamond cutoff wheel) on the lathe in the headstock, then shellac the jewel to the end of a piece of brass rod. You just hold it against the diamond lap and rotate it and it will reduce the diameter. for enlarging the center hole in the jewel, you set it up like a drilling operation with the hardened steel in the tailstock and apply diamond past(not diamatine) to the end of the rod and press and retract it into the hole slowly

[Neverenoughwatches]

2 hours ago, graemeW said:

pressed the broken one out with wood like you show. Can't quite decide if it felt like too much force for a good jewel to survive. If I have to cut it up though, I will.

I tried this earlier today with a bamboo stick, i couldn't get it to budge by hand. I used a steel pusher to force it out in the end which obviously shattered it . Under the microscope there were signs that the rubbed fold had started to tear. Hence Nev cutting the jewel out safely to prevent damage to it, and the use of the correct hand tools to draw back the brass fold to avoid any potential ripping of it. 

Edited February 4 by Neverenoughwatches

[graemeW]

1 hour ago, Neverenoughwatches said:

I tried this earlier today with a bamboo stick, i couldn't get it to budge by hand. I used a steel pusher to force it out in the end which obviously shattered it . Under the microscope there were signs that the rubbed fold had started to tear. Hence Nev cutting the jewel out safely to prevent damage to it, and the use of the correct hand tools to draw back the brass fold to avoid any potential ripping of it. 

This is it. I think the broken one came put easily purely because it was broken, allowing it to fold and come out in bits. If it came out in one piece, it would have spread the rubbed area over almost enough to get the new one it, and that doesn't happen.

I think it would take alot more force to get a jewel out in one piece.

[Neverenoughwatches]

49 minutes ago, graemeW said:

This is it. I think the broken one came put easily purely because it was broken, allowing it to fold and come out in bits. If it came out in one piece, it would have spread the rubbed area over almost enough to get the new one it, and that doesn't happen.

I think it would take alot more force to get a jewel out in one piece.

I would say the best way to remove a whole intact jewel that has a damaged or worn hole would be to intentionally break it apart and remove the pieces. Trying to force it out in one piece may risk tearing the brass fold, only once the jewel pieces are removed can the fold be then drawn back or pushed out of the way to allow room for a new jewel. I think you stand a good chance of successfully completing this with your understanding of how the process works.

 

 

2 hours ago, SwissSeiko said:

You would mount the diamond disc(an actual lapping disc, not a diamond cutoff wheel) on the lathe in the headstock, then shellac the jewel to the end of a piece of brass rod. You just hold it against the diamond lap and rotate it and it will reduce the diameter. for enlarging the center hole in the jewel, you set it up like a drilling operation with the hardened steel in the tailstock and apply diamond past(not diamatine) to the end of the rod and press and retract it into the hole slowly

I'm itching to reduce a jewel's diameter with it attached to just a graved down motor spindle, either held to a flat diamond lapping plate or reverse driven against a lapping wheel. But it's one oclock in the morning

[LittleWatchShop]

3 hours ago, SwissSeiko said:

You just hold it against the diamond lap and rotate it

Held in your hand and rotated? I was imagining some sort of precision setup.

[SwissSeiko]

5 hours ago, LittleWatchShop said:

Held in your hand and rotated? I was imagining some sort of precision setup.

Kind of. Here is a photo from Daniels book. 

 

 

Alternatively, you can use a table and a lap to do it, as seen below.

 

 

Ideally, you would use a smaller lap mounted in a milling arbor above the jewel while it is in a shellac chuck in the lathe.

Edited February 5 by SwissSeiko

[nevenbekriev]

A lot of reading here this morning.

Yes, the rubbed jewels rarely come out by pushing them. They will break rather than get out intact.

One way to get jewel out is to use cutter or graver to cut the rubbed fold above the jewel. This of course can be done on the lathe while the part with the jewel is in face plate, but it is much more simpler to do it by hand while scrubbing the fold with cutting edge of the cutter.

Well, another obvious destructive way is to etch the part. FeCl3 will do it easy. The jewel will start wobble in the 'nest' first so one will have to check when the etching is enough for the jewel to come out wit slight pushing. Searching for the jewel on the bottom of the vessel will be possible but the solution is not transparent.

Reaming the hole to use press fit jewel is another good solution, but it is easier applicable  for the balance cock than for the plate. This is because the direction of preparing the nest for the stone - on the plate it is done from outside and the hole that will be needed to cut the entire nest is huge, so huge stone will be needed. That's why bushing is used in this case. Even for the cock often there is not enough 'meat' so again bushing is needed.

About lapping stones with diamond plate - the easiest way is to glue the jewel on the face of a rod in the spindle of the lathe. Of course, small motor like from some toy or tape recorder or VHS player.... can be used and the tip of the shaft can be turned by rotating the motor. A screw fixed in the threaded hole for motor fixing and You have rest for the cutter, supply the motor and  You have lathe. You can turn a balance staff right from the motor shaft... When the jewel is glued on the face, rotate the motor and use the diamond plate as a file (move it forward/reverse) to grind the jewel. Holding the plate still will do the job much harder. You don't need polished surface here, so grit 1000 is OK.

I don't know how big a lathe should be as to be too big for watchmaking. I for sure use what they call 'mini lathe', which for sure is not watchmakers lathe and is 70-80 cm long. People often don't believe, but I can turn balance staff on it for the smallest lady's callbres and I am pretty sure that if I try, will do it on every big industrial lathe. If You put something like T-rest before the rotating piece, You can do all needed.

 

[caseback]

16 minutes ago, nevenbekriev said:

and I am pretty sure that if I try, will do it on every big industrial lathe. If You put something like T-rest before the rotating piece, You can do all needed.

I'm sure you can, but getting in up close with a loupe and my hands (especially if you don't have a collet chuck) would get some part of my anatomy puckered up...

[Neverenoughwatches]

41 minutes ago, caseback said:

I'm sure you can, but getting in up close with a loupe and my hands (especially if you don't have a collet chuck) would get some part of my anatomy puckered up...

I will advise NOT to dress smart...wearing a tie Cees

[caseback]

24 minutes ago, Neverenoughwatches said:

1 hour ago, caseback said:

I'm sure you can, but getting in up close with a loupe and my hands (especially if you don't have a collet chuck) would get some part of my anatomy puckered up...

I will advise NOT to dress smart...wearing a tie Cees

I stopped wearing those some 30 years ago. My work brings me to a lot of machineshops. Stepping inside those wearing a tie immediately gets you put in the "total waste of space" category by the shop owners (and rightly so..).