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SkinnyPupp · 03-19-2025, 05:50 AM

So today I learned how technical communication sheets can vary based on manufacturer. Some are good, some are really bad.

The movement I'm working on is a Chinese clone of the ETA 2824-2. An even more common clone (probably more than ETA itself by now) is the Sellita SW200-1. That was the easier document to find, so I used it.

This is the part I got to before losing the spring:

If you can follow along, it gives you the order of parts installed. I cropped out the relevant parts - they start with 420 (crown wheel), screw it in with 5420 (crown wheel screw) then 425 (click) and 430 (click spring)

Let me tell you now - to do it in this order is literally impossible. You can probably tell from the picture itself - once the crown wheel is installed, there's no way you can install anything underneath it. I don't know what they're thinking. At this point, experience would kick in and a watchmaker would use that to choose the correct order. But the whole point of a manual is that you shouldn't need to use intuition or guesses.

Here's the ETA version:

It starts with 17 (click) and then 18 (click spring) followed by 19 (crown wheel) and 902 Var (crown wheel screw). Based on videos, it's easier to install the spring before the click, but this at least is physically possible (this is the method I tried, using a technique I would with the 6497-2 I worked on a million times, and lost the spring). Also the graphic is clearer and easier to follow.

Anyway, there's my .. learning how to deal with poorly designed technical documents. Needless to say, I'll be using the ETA one from now on

Eventually I'll have the experience to know that something is fucky.

I'll put everything together tomorrow except for the crown wheel/click mechanism, but the watch won't wind until I get that click spring in. That will be Friday at earliest.

And then I'll tear it down and reassemble a few dozen times until it's automatic for me. LFG!

(oh yeah, this thread is going to be filled with random bullshit like this)

03-19-2025, 05:50 AM	#75
SkinnyPupp Hacked RS to become a mod Join Date: Feb 2002 Location: Sunny Hong Kong Posts: 55,065 Thanked 25,874 Times in 9,093 Posts Failed 1,573 Times in 719 Posts Member's Picture Albums	So today I learned how technical communication sheets can vary based on manufacturer. Some are good, some are really bad. The movement I'm working on is a Chinese clone of the ETA 2824-2. An even more common clone (probably more than ETA itself by now) is the Sellita SW200-1. That was the easier document to find, so I used it. This is the part I got to before losing the spring: If you can follow along, it gives you the order of parts installed. I cropped out the relevant parts - they start with 420 (crown wheel), screw it in with 5420 (crown wheel screw) then 425 (click) and 430 (click spring) Let me tell you now - to do it in this order is literally impossible. You can probably tell from the picture itself - once the crown wheel is installed, there's no way you can install anything underneath it. I don't know what they're thinking. At this point, experience would kick in and a watchmaker would use that to choose the correct order. But the whole point of a manual is that you shouldn't need to use intuition or guesses. Here's the ETA version: It starts with 17 (click) and then 18 (click spring) followed by 19 (crown wheel) and 902 Var (crown wheel screw). Based on videos, it's easier to install the spring before the click, but this at least is physically possible (this is the method I tried, using a technique I would with the 6497-2 I worked on a million times, and lost the spring). Also the graphic is clearer and easier to follow. Anyway, there's my .. learning how to deal with poorly designed technical documents. Needless to say, I'll be using the ETA one from now on Eventually I'll have the experience to know that something is fucky. I'll put everything together tomorrow except for the crown wheel/click mechanism, but the watch won't wind until I get that click spring in. That will be Friday at earliest. And then I'll tear it down and reassemble a few dozen times until it's automatic for me. LFG! (oh yeah, this thread is going to be filled with random bullshit like this)