I was planning on getting some watch cases made sometime next year, I've designed and 3d printed to check fits with the movement, geared toward a 3d resin printer, so will need slightly altered to suit CNC. What size of screw threads did you use for the case back? I have designed it for M1, but I think the 3D hubs site recommends not to go below M4 for stainless, and obviously that's a bit too big for a watch case. My case is designed to fit the ETA2824/SW200 movement, more or less the same as in your original watch. I'd be interested to know how you set up for the front and back crystals, is it a straight 90 degree fitting or is it undercut or angled in anyway? My case is designed for a 32mm glass, though I'm not too sure of the size of gasket and actual opening for the glass, I think the wall thickness for the i-gasket is 0.7mm, so the overall opening would be about 33.4? Also, I was planning a H7/p6 press fit for the bezel. Is this possible with CNC? Sorry for all the questions, I struggle to find people that have the actual knowledge to help, as I'm pretty much winging it myself, haha.
Hey Paul, Thanks a lot for reaching out ! You seem to be super passionate about watches too, that’s super great, don’t apologize for the questions :smile: Regarding the back, I used another back plate I already had from another project, but what I know for sure is that the screws are M1.2mm. It is quite tricky and not everyone can tap such small threads on SS indeed, so we had to make sure with the machinists that they could machine it properly before making it, so it should be possible if one of our engineers assists you and takes a look to put you in touch with the right team for the job ! Well spotted for the movement, my original watch indeed uses an ETA-2824-2 to be precise, but that movement is much smaller compared to the inner diameter of the case, so you would need an adapter (which I didn’t want to have to deal with for this design), but it is a great movement (also, there’s lot of information and standard parts available for it, which is always great when experimenting !) For the front crystal fit (probably what took me the longest time figuring out, I have to admit), I went with a regular sapphire (35.50mm) with a bevel on it, and it’s mounted with an “I” gasket that came with the glass. I first measured the glass with the gasket mounted on it (36.25mm) and then had the case machined with a diameter 0.15 to 0.20mm smaller than that (some people recommend only 0.1mm, but I wasn’t comfortable enough for a first try). In the end, the diameter came back at 36.07, which made the glass and the gasket press fit reasonably well (I didn’t take a glass fitting press and made a custom screw-press, but I would recommend getting one if you want to do a proper job without damaging the parts). For the bezel, an H7p6 fit should be totally possible tolerance-wise with us, if the geometry is reasonably easy, and done mostly on turning. Of course you should in that case select our “tight tolerance” option (I would also recommend calling out the actual tolerances in microns instead of p or H on your drawings). Personally though, I would probably start with an H7g6 or equivalent for the first prototypes, maybe use watch-grade glue to test the assembly, and then move to a stronger fit when you have a press to properly assemble the 2 parts. Or even do with a less tight tolerance and just mention that the 2 parts must assemble (you gain on cost, but lose on repeatability and precision of the fit). Let me know if any other questions, would love to see more of your project ! - Antoine
@@ProtolabsMFG thanks for your reply and the info. I'll look into the gasket and fitting options, I have a crystal/case press and have assembled an eBay bought watch case with a press fit, so I'm comfortable with the assembly. Once I've got my design redrawn and decided on final dimensions etc., I'll be in touch. If you would like a look at my rough designs so far, look at phi_watches on Instagram, as I've been documenting my progress (and confusion) on that.
@@Saltcoatsbhoy Were are happy to help! your insta looks cool. It's on our featured list for @3dhubs :) When you have your dimensions and design 'done' you can upload and play with all kinds of features and get an instant quote (for free) on our platform. Just something that might help when making design decisions. www.3dhubs.com/manufacture/?technology=cnc-machining
I dont mean to be so off topic but does anybody know a trick to get back into an instagram account?? I was dumb forgot the login password. I appreciate any help you can give me
@Gary Ali thanks so much for your reply. I found the site through google and I'm in the hacking process atm. I see it takes quite some time so I will reply here later when my account password hopefully is recovered.
Hey William! Thanks for the compliment and this should answer your question: -The theory of Horology, Charles-Andre Reymondin, 1999 - contains some technical drawings for watches, great for holistic context. - Watchmaking, by George Daniels - contains more details about Casemaking. - Beginner Watchmaking, Tim A Swike - focused more on assembly and maintenance, contains a lot of pictures. - We also recommend this TH-cam channel on assembly instructions, this one for the glass (French, autosubs), as well as NIHS standards for watchmaking. th-cam.com/video/AvKvY7SmlM0/w-d-xo.html&%3Bab_channel=NicolasGadrat
Awesome video... I may have this backwards but I want to clarify. Is 316ss easier to hold tolerances and flatness than 304ss? Also for corrosion, our parts go in waterlines and sewers, you said 304ss is more corrosion resistant?
Hi! 316 generally has a higher resistance to corrosion than 304, as it has more zinc and molybdenum in it, so 316 would a better choice than 304 corrosion-wise. Mechanically, however, the 2 alloys are pretty similar, so you won’t hold a better flatness per se with 316 compared to 304. Worth noting that 316 is much harder to machine though, so in a nutshell, you probably want to make sure that it’s really needed for your application.
Pretty nice video and an excellent explanation of types of stainless steel. Thank you for explaining the uses of it.
Thanks! Glad you liked it.
I want those books!
I was planning on getting some watch cases made sometime next year, I've designed and 3d printed to check fits with the movement, geared toward a 3d resin printer, so will need slightly altered to suit CNC. What size of screw threads did you use for the case back? I have designed it for M1, but I think the 3D hubs site recommends not to go below M4 for stainless, and obviously that's a bit too big for a watch case. My case is designed to fit the ETA2824/SW200 movement, more or less the same as in your original watch. I'd be interested to know how you set up for the front and back crystals, is it a straight 90 degree fitting or is it undercut or angled in anyway? My case is designed for a 32mm glass, though I'm not too sure of the size of gasket and actual opening for the glass, I think the wall thickness for the i-gasket is 0.7mm, so the overall opening would be about 33.4? Also, I was planning a H7/p6 press fit for the bezel. Is this possible with CNC?
Sorry for all the questions, I struggle to find people that have the actual knowledge to help, as I'm pretty much winging it myself, haha.
Hey Paul, Thanks a lot for reaching out ! You seem to be super passionate about watches too, that’s super great, don’t apologize for the questions :smile:
Regarding the back, I used another back plate I already had from another project, but what I know for sure is that the screws are M1.2mm. It is quite tricky and not everyone can tap such small threads on SS indeed, so we had to make sure with the machinists that they could machine it properly before making it, so it should be possible if one of our engineers assists you and takes a look to put you in touch with the right team for the job !
Well spotted for the movement, my original watch indeed uses an ETA-2824-2 to be precise, but that movement is much smaller compared to the inner diameter of the case, so you would need an adapter (which I didn’t want to have to deal with for this design), but it is a great movement (also, there’s lot of information and standard parts available for it, which is always great when experimenting !)
For the front crystal fit (probably what took me the longest time figuring out, I have to admit), I went with a regular sapphire (35.50mm) with a bevel on it, and it’s mounted with an “I” gasket that came with the glass. I first measured the glass with the gasket mounted on it (36.25mm) and then had the case machined with a diameter 0.15 to 0.20mm smaller than that (some people recommend only 0.1mm, but I wasn’t comfortable enough for a first try). In the end, the diameter came back at 36.07, which made the glass and the gasket press fit reasonably well (I didn’t take a glass fitting press and made a custom screw-press, but I would recommend getting one if you want to do a proper job without damaging the parts).
For the bezel, an H7p6 fit should be totally possible tolerance-wise with us, if the geometry is reasonably easy, and done mostly on turning. Of course you should in that case select our “tight tolerance” option (I would also recommend calling out the actual tolerances in microns instead of p or H on your drawings). Personally though, I would probably start with an H7g6 or equivalent for the first prototypes, maybe use watch-grade glue to test the assembly, and then move to a stronger fit when you have a press to properly assemble the 2 parts. Or even do with a less tight tolerance and just mention that the 2 parts must assemble (you gain on cost, but lose on repeatability and precision of the fit).
Let me know if any other questions, would love to see more of your project !
- Antoine
@@ProtolabsMFG thanks for your reply and the info. I'll look into the gasket and fitting options, I have a crystal/case press and have assembled an eBay bought watch case with a press fit, so I'm comfortable with the assembly. Once I've got my design redrawn and decided on final dimensions etc., I'll be in touch. If you would like a look at my rough designs so far, look at phi_watches on Instagram, as I've been documenting my progress (and confusion) on that.
@@Saltcoatsbhoy Were are happy to help! your insta looks cool. It's on our featured list for @3dhubs :) When you have your dimensions and design 'done' you can upload and play with all kinds of features and get an instant quote (for free) on our platform. Just something that might help when making design decisions. www.3dhubs.com/manufacture/?technology=cnc-machining
Are you cut these stanlees steel items by your Stepcraft D series?
Hi Gents, thank you very much for the video, very instructive ! I wanted to ask which SS has been used to make the watch case ? Thanks again. Cheers !
I dont mean to be so off topic but does anybody know a trick to get back into an instagram account??
I was dumb forgot the login password. I appreciate any help you can give me
@Gary Ali thanks so much for your reply. I found the site through google and I'm in the hacking process atm.
I see it takes quite some time so I will reply here later when my account password hopefully is recovered.
@Gary Ali it worked and I now got access to my account again. I'm so happy:D
Thanks so much you saved my ass :D
@Roberto Quinton No problem xD
Good video! May I ask the books you referenced for the watch designs and rules/guidelines?
Hey William! Thanks for the compliment and this should answer your question:
-The theory of Horology, Charles-Andre Reymondin, 1999 - contains some technical drawings for watches, great for holistic context.
- Watchmaking, by George Daniels - contains more details about Casemaking.
- Beginner Watchmaking, Tim A Swike - focused more on assembly and maintenance, contains a lot of pictures.
- We also recommend this TH-cam channel on assembly instructions, this one for the glass (French, autosubs), as well as NIHS standards for watchmaking. th-cam.com/video/AvKvY7SmlM0/w-d-xo.html&%3Bab_channel=NicolasGadrat
Awesome video... I may have this backwards but I want to clarify. Is 316ss easier to hold tolerances and flatness than 304ss?
Also for corrosion, our parts go in waterlines and sewers, you said 304ss is more corrosion resistant?
Hi! 316 generally has a higher resistance to corrosion than 304, as it has more zinc and molybdenum in it, so 316 would a better choice than 304 corrosion-wise.
Mechanically, however, the 2 alloys are pretty similar, so you won’t hold a better flatness per se with 316 compared to 304. Worth noting that 316 is much harder to machine though, so in a nutshell, you probably want to make sure that it’s really needed for your application.