Order CNC machined movement parts

[anda3243]

Has anyone had some movement parts made by a CNC shop and made a successful repair? 

I am new to this hobby, I still have lots to learn. But it seems that many beautiful watches end up not working or as part donors because some part is lost or broken. 

Has anyone tried to make a CAD drawing of for example a bridge and had a CNC shop mill it make it? I know it needs to be specialized CNC shop that can work such small parts, but there are several in China and elsewhere.  Making a CAD model is not hard, making a drawing is not hard, understanding the necessary tolerances can be a challenge, but I think it can be done. 

Would it make sense to buy a job lot of watches where critical components are missing or broken and try to fix them using this CNC route? It would be a cool way to add to ones collection, and maybe make a buck.

I have not found anything CNC related on this forum. I have found several threads where some part is made on a lathe (quite antique looking one) or a spring is filed out of a blank. But these methods are time consuming, and limited to relatively simple shapes.

Thank you for your answers and comments!

[nickelsilver]

I use a CNC milling machine almost daily to make watch parts. Both for prototypes and for repairs. An example of repair was 2 sets of  minute counter wheels complete, for Valjoux 71. The customer couldn't find spares anywhere, so were willing to pay to get these watches functional.

 

4 different components (per wheel), 4 different drawings, a fair bit of time spent on the measuring microscope and profile projector to get the info needed for those drawings. 3 made on CNC, one of those then cut with a gear cutting machine (with specialized cutter of course), one turned on the lathe. 3 of them heat treated, then finished as needed; for example the arbor has the pivots burnished, all other features polished, there are 3 critical diameters that are kept easily within a few microns. The heart cam is mirror polished on its perimeter. Counterweight is grained. The wheel has a circle grained finish (and is beryllium copper).

 

Not sure if there's a Chinese company that will make one or two parts? If there is, and they can hit the tolerances, then making a drawing that's bang-on is quite a bit of work. Not sure if it would be worthwhile for watches that can be bought as "job lots". Also, many watches are in need of quite particular components like escapement parts, or jewel assemblies, that are made by specialist firms with decades of experience and $$$ in equipment.

 

But even some "worthless" watches are worth it to their owner to pay for the repair even with expensive part fabrication. Did a cylinder for a cylinder escapement a couple weeks ago, the full repair cost was probably 10x what the piece is worth.

 

 

Edited February 25, 2023 by nickelsilver

[Nucejoe]

2 hours ago, nickelsilver said:

I use a CNC milling machine almost daily to make watch parts. Both for prototypes and for repairs. An example of repair was 2 sets of  minute wheel counter wheels complete, for Valjoux 71. The customer couldn't find spares anywhere, so were willing to pay to get these watches functional.

 

4 different components (per wheel), 4 different drawings, a fair bit of time spent on the measuring microscope and profile projector to get the info needed for those drawings. 3 made on CNC, one of those then cut with a gear cutting machine (with specialized cutter of course), one turned on the lathe. 3 of them heat treated, then finished as needed; for example the arbor has the pivots burnished, all other features polished, there are 3 critical diameters that are kept easily within a few microns. The heart cam is mirror polished on its perimeter. Counterweight is grained. The wheel has a circle grained finish (and is beryllium copper).

 

Not sure if there's a Chinese company that will make one or two parts? If there is, and they can hit the tolerances, then making a drawing that's bang-on is quite a bit of work. Not sure if it would be worthwhile for watches that can be bought as "job lots". Also, many watches are in need of quite particular components like escapement parts, or jewel assemblies, that are made by specialist firms with decades of experience and $$$ in equipment.

 

But even some "worthless" watches are worth it to their owner to pay for the repair even with expensive part fabrication. Did a cylinder for a cylinder escapement a couple weeks ago, the full repair cost was probably 10x what the piece is worth.

 

 

How do manufaturers polish cams?  Different process  than you do for single piece I suppose. 

[praezis]

Wow, phantastic work!

I have flat parts made by CNC laser fine cutting.

Most work is measuring and making the CAD drawing. But my laser comp can do even this for a reasonable price. 

 

[nickelsilver]

28 minutes ago, Nucejoe said:

How do manufaturers polish cams?  Different process  than you do for single piece I suppose. 

Nowadays they would almost certainly do electrolytic polishing in batches and call it good. Back in the day I'm quite sure the cams were mounted on little holders and the worker- most likely women- ran them handheld against motorized laps, expertly, all day long.

 

 

Same for pinions. Now it's all electrolytic (with some rare exceptions). Back in the day, even a lowly AS mass produced hum-drum caliber would have the pinion leaves polished with wood laps, tip to root, stunningly. Pivots roll burnished, always. Now the pivots are generally roll burnished? Pretty sure? They sure don't wear like the old stuff. That is, they wear faster.

 

For parts like these I hold them in a little tiny vice under the microscope and take the cutting marks out with 20 or 12 micron abrasive paper on a flat steel handle, work down to 3 micron then final polish with either 1 micron paper or with wood and steel polishing paste in a hand motor. Have to keep turning the part in the vice of course, haha!

 

For pinions, if it's not ultra high grade or just preliminary prototype work, I hold the pinion between centers (often an old truing caliper), then with about a 20mm radial bristle brush running in the lathe with steel polishing paste, bring the leaves up to the brush. If you get it right they auto-index kind of like with a rounding up tool (or a wood lap pinion leaf polisher). Get them to index both ways a few revolutions, flip 180 degrees, same. You can get quite a good finish on the functional part. You won't have a crisp face. For really high end stuff I'll drag out the pinion leaf polisher and dress a wood lap for the pinion- it's different for every module- and spend the time necessary.

Edited February 25, 2023 by nickelsilver

[anda3243]

13 hours ago, nickelsilver said:

Not sure if there's a Chinese company that will make one or two parts? If there is, and they can hit the tolerances, then making a drawing that's bang-on is quite a bit of work. Not sure if it would be worthwhile for watches that can be bought as "job lots". Also, many watches are in need of quite particular components like escapement parts, or jewel assemblies, that are made by specialist firms with decades of experience and $$$ in equipment.

 

But even some "worthless" watches are worth it to their owner to pay for the repair even with expensive part fabrication. Did a cylinder for a cylinder escapement a couple weeks ago, the full repair cost was probably 10x what the piece is worth.

Thank you for sharing your beautiful work! It really looks amazing!

Do you have an inhouse CNC machine? Or you some CNC shop? Is it a specialized CNC machine for watchmaking?

I have used several Chinese CNC shops for somewhat larger parts (25 to 300mm). There are many that are willing to do 1 parts or small batches. In different price levels and quality levels of course. However I am sure there are some working with really smal parts as well. Have not looked that closely.

Ebay job lots might not be the best start, you are right, I think they often know exactly what they are selling. I will find a local watchmaker and see if he has something that he does not want to fix because of missing or broken part.

11 hours ago, nickelsilver said:

 

Same for pinions. Now it's all electrolytic (with some rare exceptions). Back in the day, even a lowly AS mass produced hum-drum caliber would have the pinion leaves polished with wood laps, tip to root, stunningly. Pivots roll burnished, always. Now the pivots are generally roll burnished? Pretty sure? They sure don't wear like the old stuff. That is, they wear faster.

 

For parts like these I hold them in a little tiny vice under the microscope and take the cutting marks out with 20 or 12 micron abrasive paper on a flat steel handle, work down to 3 micron then final polish with either 1 micron paper or with wood and steel polishing paste in a hand motor. Have to keep turning the part in the vice of course, haha!

 

For pinions, if it's not ultra high grade or just preliminary prototype work, I hold the pinion between centers (often an old truing caliper), then with about a 20mm radial bristle brush running in the lathe with steel polishing paste, bring the leaves up to the brush. If you get it right they auto-index kind of like with a rounding up tool (or a wood lap pinion leaf polisher). Get them to index both ways a few revolutions, flip 180 degrees, same. You can get quite a good finish on the functional part. You won't have a crisp face. For really high end stuff I'll drag out the pinion leaf polisher and dress a wood lap for the pinion- it's different for every module- and spend the time necessary.

Thank you for sharing these details. Seems that the most time consuming part is the final finishing and polishing. 

11 hours ago, praezis said:

Wow, phantastic work!

Yes, it really is!

11 hours ago, praezis said:

I have flat parts made by CNC laser fine cutting.

Most work is measuring and making the CAD drawing. But my laser comp can do even this for a reasonable price.

This seems like something I could start with. And it looks like a part that is prone to breaking. Do you use a stainless spring steel for the replacement part? Or carbon steel? I assume that there is no heat treatment, the sheet is of spring steel in hardened state before laser cutting?

[grsnovi]

23 hours ago, anda3243 said:

Has anyone had some movement parts made by a CNC shop...

...it seems that many beautiful watches end up not working or as part donors because some part is lost or broken. 

I think (for the most part) the majority of the folks here are watch repair enthusiasts. If we can't source a part from a donor - we keep looking and work on something else in the mean time.

The cost to outsource a one-off part to exacting tolerances would be cost prohibitive (unless you are doing so for a deep-pocketed client). While there are a few here who are in fact doing that level of watchmaking after lurking here for just about a year I think the number is small.

There are a large number of first timers who have watched a lot of YouTube and who think they'd like to take that beautiful antique that grandpa kept in the drawer and make it go again (or who'd like to service their own $10,000. watch rather than pay $800. to have it serviced).

Many of us have landed here later in life and the reality of learning about watches and then subsequently deciding that we need to also be precision machinists is likely not going to happen.

- Gary 

[JohnR725]

18 hours ago, nickelsilver said:

CNC milling machine

as nice as the pictures are of the parts how about a picture of the machines?

 

[Neverenoughwatches]

6 hours ago, grsnovi said:

I think (for the most part) the majority of the folks here are watch repair enthusiasts. If we can't source a part from a donor - we keep looking and work on something else in the mean time.

The cost to outsource a one-off part to exacting tolerances would be cost prohibitive (unless you are doing so for a deep-pocketed client). While there are a few here who are in fact doing that level of watchmaking after lurking here for just about a year I think the number is small.

There are a large number of first timers who have watched a lot of YouTube and who think they'd like to take that beautiful antique that grandpa kept in the drawer and make it go again (or who'd like to service their own $10,000. watch rather than pay $800. to have it serviced).

Many of us have landed here later in life and the reality of learning about watches and then subsequently deciding that we need to also be precision machinists is likely not going to happen.

- Gary 

I do agree that depending on one's background that the skill for even basic watchrepair can be initially underestimated. But watchrepair has many levels and a watchpart replacement skill can still restore many watches to a working condition. 

[nickelsilver]

7 hours ago, JohnR725 said:

as nice as the pictures are of the parts how about a picture of the machines?

 

Ah ok- but only because you asked, John.

 

That's my CNC. Put it together about 13 years ago, I figure it runs about 1000 hours per year, so it seems to have turned out pretty solid! Built on a Schaublin 102 short bed, with a Swiss X/Y slide with Rollvis zero backlash screws, DC servo motors, and a control built by a Hungarian guy (in Hungary). It repeats on location under 5 microns, which is plenty good. It has 100mm travels, which so far has been enough. The spindle is a Swiss Gepy, it can do 15k rpm but it's had a hard life, so I keep it at 11k. That's still a bit slow for the small cutters (down to 0.2mm) but it does OK.

 

That's my Sixis 101 mill, I use it for all my gear cutting as well as general milling. There are 3 different dividing spindles, one for Sixis plates, another for the stacks of brass plates, and another that's universal.

 

A Sallaz pivot burnisher; it's a production machine, and I found for the small runs I do it works better with a hand crank, like a Pivofix that went to the gym.

 

Profile projector, mostly used for checking gearing and gear cutters, but lots of other things too. 10,20,50 and 100x magnification.

 

That's a jig boring machine, which see lots of use but I include it as I often use it as a measuring microscope. Made by Dixi (another to the right by Hauser).

 

Hauser measuring microscope, I have several lenses but use 50x all the time.

 

And my most treasured machine (there are lots of others, haha), my 8mm lathe. It's a Leinen WW82, with a Levin cross slide, with the X screw switched out for one from a Schaublin 70. I use it several times per day, sometimes all day, sometimes all day for days in a row!

Edited February 26, 2023 by nickelsilver

[tomh207]

I think the biggest problem asking a CNC shop to do one off jobs is when you casually mention your tolerance requirements are 1 microns or less. A jobbing shop outside of the aerospace or watch industry (maybe formula 1 teams too) are unlikely to have the high accuracy machinery to cope with this. Laser cutting might be a possibility for flat parts in the keyless works but not for much else. An example for me was researching into pad printing for dials, a cliche for the pad printer to do a dial was quoted as £80.  
 

I think it would only be viable if you were ordering a batch runn of 100-300 parts and hope you can sell the excess. I have also looked into CNC desktop machines, not at this level of accuracy requirements, the cheapest I could find that would have been useful for what I wanted to do was going to be £2500.00 + VAT. I went off that idea for some reason . The cheaper hobby level CNC machines just don’t have the required rigidity.

 

even with CNC you are still going to have a few hours of finishing work to do.

 

Tom

 

[nickelsilver]

31 minutes ago, tomh207 said:

even with CNC you are still going to have a few hours of finishing work to do.

 

Tom

 

This is a big deal. I just ran a batch of 12 escape cocks for a customer, total machine time for doing both sides is about 3 hours for the batch. Then the sides get grained, the edges beveled and polished, the sinks around the jewel and screw cut and polished, and finally they get cotes de geneve striping. Even without the last bit, it adds up to much more time than the CNC work. Though, if I had to do them completely manually it would be days of work before the finishing starts!

 

1 hour ago, Neverenoughwatches said:

I do agree that depending on one's background that the skill for even basic watchrepair can be initially underestimated. But watchrepair has many levels and a watchpart replacement skill can still restore many watches to a working condition. 

There are very, very few watchmakers who actually make parts. You do learn to make some things in school, like staffs and stems, and some schools even do some gear cutting, but once in the real world doing repair at the bench, probably 99.99% never make a part.

 

It's a matter of time and money; if you have excellent equipment for part making all set up and ready to go, and do it often enough that you're never "rusty", it might make sense, but most good watchmakers have so much work doing stuff that you can find parts for, it would be a loss to stop and make a staff or stem, even if they priced it out the stratosphere. Just doesn't make sense.

 

I think there are, (and were, even prior to Youtube), more serious hobbiests making components than professionals. They have the time and desire to do it, and often do very good work. The school I used to teach for last century did a number of 1 week courses on a variety of watchmaking subjects, and they were often attended by hobbiests. I saw some excellent work from many of them.

[praezis]

13 hours ago, anda3243 said:

Do you use a stainless spring steel for the replacement part? Or carbon steel? I assume that there is no heat treatment, the sheet is of spring steel in hardened state before laser cutting?

I used both, but with stainless you can avoid the needed nickel plating. No additional hardening required. My laser cutter however also offers a special Swiss stainless alloy that can be further hardened after cutting by keeping at high temperature for some hours.

Frank

[JohnR725]

9 hours ago, nickelsilver said:

There are very, very few watchmakers who actually make parts. You do learn to make some things in school, like staffs and stems, and some schools even do some gear cutting, but once in the real world doing repair at the bench, probably 99.99% never make a part.

I think you'll find that the schools are slowly decreasing teaching anything involving making. My understanding the US that a lot of the two-year programs are going away in favor of one year technician programs. Even the local college teaching the Rolex program has trimmed an entire quarter off which basically would've been making stuff in favor of not making stuff. I know they still make some items but they don't spend so much time making watch components.

then even if the watchmaker has training in making stuff and can make stuff there is so much watch work out there because there's a shortage of watch repair people there is no need to actually make anything at all. Then even if you did how many customers we willing to pay for it.

 

10 hours ago, tomh207 said:

Laser cutting might be a possibility for flat parts in the keyless works but not for much else.

the problem with a laser cutter is it gets hot, very hot and vaporizes things but can leave a burnt edge. Seal definitely have to do finishing but they are really nice for well square holes are really nice. Francis of I need a square hole in a mainspring I ask it work nicely and somebody might cut a square hole for me they do engraving where I work and they have a fiber laser that will cut metal. Occasionally I've needed something a little thicker than a mainspring and it definitely gets a burnt edge to it so that refinishing is a must

probably rather than a laser wire EDM machine. With a vantage of you can cut Springs steel that's already nice and springy and not worry about it getting hot like it would know laser and they finished should be relatively good. So the absolute perfect I think for setting and keyless components.

10 hours ago, nickelsilver said:

It's a matter of time and money; if you have excellent equipment for part making all set up and ready to go, and do it often enough that you're never "rusty", it might make sense, but most good watchmakers have so much work doing stuff that you can find parts for, it would be a loss to stop and make a staff or stem, even if they priced it out the stratosphere. Just doesn't make sense.

 

I think there are, (and were, even prior to Youtube), more serious hobbiests making components than professionals. They have the time and desire to do it, and often do very good work. The school I used to teach for last century did a number of 1 week courses on a variety of watchmaking subjects, and they were often attended by hobbiests. I saw some excellent work from many of them.

the problem with using CNC to make watch parts is from the outside it looks like a wonderful thing to do. But if you were to purchase the equipment new it's astronomically expensive and you'd probably never be able to justify it unless you are in a factory setting. Then you can't just lay the part on top of the machine have it digitize it and make the part for you it's a little more complicated. then you end up with a whole bunch of different skill sets like understanding how to program the machine understanding how to machine parts basically way too much knowledge skills and money typical watchmakers don't have. Plus as stated above typical watchmakers today are buried in work and don't need to deal with CNC.

the hobbyist aspect is interesting because hobbyist can have different backgrounds before they got in the watch and clock repair. They have prior knowledge of machining CNC and they may be doing it later in life when they have more money. So in other words it's more of a fun project then everything changes especially if they can make their own equipment.

 

 

 

 

 

[anda3243]

15 hours ago, nickelsilver said:

That's my CNC. Put it together about 13 years ago,

Really amazing  . Thank you for sharing! 

 

15 hours ago, tomh207 said:

I think the biggest problem asking a CNC shop to do one off jobs is when you casually mention your tolerance requirements are 1 microns or less. A jobbing shop outside of the aerospace or watch industry (maybe formula 1 teams too) are unlikely to have the high accuracy machinery to cope with this

I will do a casual search and see what comes up. As soon as I find some time. 

22 hours ago, grsnovi said:

There are a large number of first timers who have watched a lot of YouTube and who think they'd like to take that beautiful antique that grandpa kept in the drawer and make it go again

I think I have found a place where to get a new ETA-2824 movement for 12 USD, Made in china obviously, but maybe a good place to start. 

 

Thanks everyone for sharing your experiences!

[grsnovi]

37 minutes ago, anda3243 said:

maybe a good place to start. 

After no luck with a number of eBay movements I broke down and purchased a Seagull ST36. I was doing fine until I dissolved the glue they use (instead of a tiny taper pin) to hold the balance spring to the balance cock. So, be careful with how you go about cleaning your new movement.

[Nucejoe]

23 hours ago, grsnovi said:

I think (for the most part) the majority of the folks here are watch repair enthusiasts. If we can't 

There are a large number of first timers who have watched a lot of YouTube and who think they'd like to take that beautiful antique that grandpa kept in the drawer and make it go again (or who'd like to service their own $10,000. watch rather than pay $800. to have it serviced).

Many of us have landed here later in life and the reality of learning about watches and then subsequently deciding that we need to also be precision machinists is likely not going to happen.

- Gary 

ye,  First screw driver I bought, thought  I need a pair of tweezers too to modify George Daniels watches.

[grsnovi]

10 hours ago, Nucejoe said:

to modify George Daniels watches.

Have you worked on one of his?

[Nucejoe]

10 minutes ago, grsnovi said:

Have you worked on one of his?

I tell you, had I bought a staking set too , would have felt confident to teach him watchmaking and design.

Impressive Co-axial.      WOW.   

Rgds 

[grsnovi]

4 hours ago, Nucejoe said:

would have felt confident to teach him watchmaking and design.

LOL  

[Klassiker]

Watchguyuk uses CNC in his watch repair business. He might be prepared to offer advice and support, if you contact him via his website.

[anda3243]

On 2/25/2023 at 11:18 PM, nickelsilver said:

Nowadays they would almost certainly do electrolytic polishing in batches and call it good. Back in the day I'm quite sure the cams were mounted on little holders and the worker- most likely women- ran them handheld against motorized laps, expertly, all day long.

Has anyone tried electropolishing at home? It seems to be not very difficult. Maybe electropolishing + finishing by hand? 

It is not fun to deal with acids, but only a small amount is needed for these small parts.