I've got a list in the main post about what parts will work best iirc. I think most common is going to be the AP movement though that will need a new date wheel, rep bracelet, and then I would expect to see service hands/dials from those who don't already have vintage stuff.This is a very interesting project - looking forward to see some amazing 3700 frankens.
Which parts (on top of this case set) do you guys plan to use for your builds? K2121 caliber? Which dial, hands, bracelet?
Yep, I'm with you on that. I've checked with all of my usual contacts plus many more to no avail. No 3700 crystal gaskets anywhere. So I guess you're right - these are not readily available, least from the usual resellers and independent watchmakers. I can't see much added value in getting an OME gasket if the custom bezel & gasket are measured to work with the gen spec crystal. It's a question of a tolerance of 0.2-0.5mm at most I guess so I can't see how that could affect the project in real life, visually or mechanically. So, yep, I'm OK with you simply producing a custom gasket at whatever specs you find fit. Thanks for pushing this project anyway.Just thinking out loud here. I think the reason I haven’t been able to find a 3700 gasket is because they don’t exist. Or, at least, they will never be available to buy. It isn’t a product anymore.
Why? For watches 25+ years old, PP requires you to send it in to Switzerland. They will not provide parts to service centers anymore. Moreover, it’s a part that is replaced out of necessity, not aesthetic, so they don’t pop up used. Why there was ever one for sale (you can find a sold-out listing if you search for it) is beyond me.
The only instance I think I could find one is under perfect circumstances. Being that the case gaskets come in sets of 4 or 5, I presume crystal gaskets could be the same. Or maybe they came with the replacement crystal. But if they came in packs, it’s possible a now-defunct authorized service place has a spare. But from everyone I’ve spoken to who can get gen parts, they couldn’t get the crystal gasket.
So, I’m thinking I’ll put in a firm condition. If the guy I’m waiting to hear back from (should get back to me late next week) doesn’t have one, I will abandon the search so not to delay production, which is scheduled to begin Monday.
That said, if I do somehow acquire a gen gasket after the run is done, I’ll update the bezel design and see if enough people want a replacement to justify manufacturing some.
So in terms of tolerances, they do need to be tight for a good waterproof seal. Part of the cost of the CNC work is that I pushed tight tolerances in spots that matter, such as the gasket opening. The gasket should be about 0.05mm oversized to have a good compression fit at this volume. I’m also having a professional watchmaker (not just a guy who serviced stuff, this guy makes watches from scratch himself) go over the files to confirm my tolerances specifically with the crystal gasket.Yep, I'm with you on that. I've checked with all of my usual contacts plus many more to no avail. No 3700 crystal gaskets anywhere. So I guess you're right - these are not readily available, least from the usual resellers and independent watchmakers. I can't see much added value in getting an OME gasket if the custom bezel & gasket are measured to work with the gen spec crystal. It's a question of a tolerance of 0.2-0.5mm at most I guess so I can't see how that could affect the project in real life, visually or mechanically. So, yep, I'm OK with you simply producing a custom gasket at whatever specs you find fit. Thanks for pushing this project anyway.
Hey man, many thanks for the update. Not only are gen gasket impossible to source but gen crystal are equally hard to find. So hats off for your exploring alternative avenues. Please keep us posted, txs.GASKET / CRYSTAL BIG UPDATE!
I am speaking with a shop to manufacture crystals. The ebay one is NOT gen spec. But I have the files, may as well get some made! MOQ will be high, but I have a friend who is willing to take on inventory to mitigate that. eBay crystal is about $160USD, so my target price is $140USD. At the moment there are no gen crystals for sale, so this will be the best bet for most people on the run.
Now for the gaskets. The swiss place declined the project. Here is what the plan is now. As mentioned, my cnc shop can injection mold 100 for $4k. The same guy stocking crystals is up for stocking this too, so really MOQ is 50. There are 6 people on the run who need gaskets, so cost per person is around $330.
However, as this is a huge cost, I am going to buy some Hytrel filament to 3D print test gaskets. If they work perfectly that way then we can use them. I have my doubts, though. The hardness is 60 compared to the proper 72. Perhaps the added volume of this gasket compared to conventional ones will help mitigate. But at the least, testing with a printed one will help confirm the fit prior to manufacturing.