Let me preface by saying that, yes, I'm building a watch, but it's a learning exercise/labour of love, I have no intention of building an empire... With that in mind, I'll hope that you understand that I'm just an enthusiastic 'noob' with no aspirations of grandeur. I've looked at plenty of drawings, watched plenty of videos and when necessary asked questions to people who know what they're talking about. In this case, I'm just about ready to physically 'make something happen', but there's a couple of details I can't completely get my head around.
...I've done my CAD, everything looks good on paper; I'm now about to build a printed resin prototype, to check if my work is going to fit together.
1/ At some point I'm going to have to talk to a mould maker or CNC engineer about screw threads. I'm not worried about the screw-down crown and case-tube, I'm going to buy those parts in. However, the screw down case back has left me a bit mystified. Let's say the thread is 35mm with a 0.5mm pitch (standard Swiss ISO). Which radius is represented by the 35mm; is it the apex of the thread, the pit or in the middle?
2/ Securing the crown tube. As this is intended to be a Diver (CIRCA 20ATM) I'm assuming I'll have to do more than simply 'hammer in' the crown tube (as higher pressures will inevitably cause it to move). I've heard of people using solder to secure this part, but to me anyway, it sounds a bit brutal. I've not managed to find any content on drawings or build-logs that really talk about this process. What's the best way to secure the case tube?
3/ This is the question that's going to expose me (most) as a noob!!! Can someone point me in the direction (of detailed files that show the best method for securing a movement holder to the case... Most drawings just show it 'sat' on an inner lip, but obviously some mechanism needs to be in place to prevent rotation. I've seen indentations on the rings, with (potentially) corresponding screw holes/drilled holes?? in the case, and I'm pretty sure that 'clamps' have a lot to do with this, I've just not found a resource yet, that clearly illustrates how this fits together. In fairness, I'm pretty clueless on the whole 'how to prevent' rotation 'problem', including the movement itself. - I kinda understand how to stop the dial from moving. I have a 'male' extrusion on the underside and a corresponding 'female' on the case (I intend to secure with cement), but this whole science is a little alien to me (fixing the movement in the ring, and the ring in the case), so if there's a video or some reading material out there, that will help me with this, I'd be glad to hear about it.
4/ OK, last one. When looking at drawings of Diver watches, I consistently notice there's a weird double radii gasket between the bezel and the case (image attached). I'm pretty sure this isn't two gaskets (as they'd be a nightmare to fit), but I could be wrong. Equally, I can't find a part anywhere that resembles this. Any help here would be greatly appreciated.
Thanks in advance