Gen Crown

[dsp5500]

Any info on installing a Gen Auto crown into an Auto Pam? I take it will not fit in the rep crown tubes??? Are there any after market crown tubes that will work? Any info appreciated on this topic.

Regards,

Rob

[babola]

As far as I know the stock rep crown tube will require a bit of remoddeling to fit the gen auto crown. The Zigmeister springs to mind since he's installed gen auto crowns in 29 and 63 reps for few members here.

Kruzer could confirm this, of course.

cheers,

babola

[Watchmeister]

Most auto PAM's have required modest enlarging (but not destruction of) case tube. Just use fine swiss files. If you have access to a proper drill press you can yank out the existing tube and use surgical tubing. I have done both. I know Ziggy uses the files as opposed to a drill press and he has done many of them. I have not heard of anyone being unable to use the crowns for this reason though.

So far, using the file method Ziggy has installed crowns on my 24, 27, 29, 63, 196, 188 and Jimmy Cases.

[dsp5500]

Good news, After fitting is it water tight or is it just a means to get the crown sitting in the tube? In other words does it sit nice and tight like a Gen?

On another note I hope The Zigmeister is still doing work when I get my watch back from SSsurfer.

I need a lume and Gen crown install at least, I may still swap to a 028.

Rob

[Watchmeister]

I do know water resistance which is as good or better than a rep can be achieved. What I don't know is if you have to swap the outer gasket to achieve it. How it compares in terms of water resistance to a gen I can't say for sure. I have gone swimming with at least one (not diving though). I don't recommend this to anyone else and Ziggy is not in favor of it either. I just ahd to try it. If mounted properly the seal and springiness of the gen crown on the rep when the CG is opened does compare very favorably to the gen. Unfortunately that crown springing out is addictive and now I find myself changing over all of my PAM's.

Remember the gen crowns we have have the original 3 gasket stem set-up rather than the newer 2 gasket system on gens . Interestingly, Panerai seems to have used a 3 gasket system when they were making watches for the military so it must be reasonably good.

[dsp5500]

Would it be possible to get some pics of rep auto crowns and the crown tube to get a better idea on what mods are needed?

Rob

[dsp5500]

Here

[Watchmeister]

DSP-

That is the crown tube. And it can be either more or less waterproof. Your two variables are how closely you adjust the case tube and how well the gaskets seal around it. Some people have elected to change the gaskets for an even tighter seal. In that case the crown seal, anyhow, should be every bit as good as any other watch. Given that the crown springs open I would guess the seal is better than a typical rep set-up. But it is all about how well you fit the crown and ensuring that the lever pin contacts the crown and actually applies pressure on the crown. Remember that gen crowns are much deeper than the reps or the Palps. If you haven't previously shaved down the lever for a Lello or Palp 2.1 you should be fine though.

[archibald]

I believe that unless you get reallly lucky, the only way to guarantee true 1:1 water resistance that the gen has is to make a tube (my smith uses a lathe but I see no reason why the right size of surgical tubing, a set of files and a steady hand can't produce the same result). There are three considerations:

1)the interior dameter should be the same size as the gaskets on the neck of the crown ( about 2.35mm).

2)The part that protrudes from the case should be a fraction of a mm smaller than diameter of the recess in the underside of the crown. (4.75mm..I THINK.)

3)the tube should stick out of the case just far enough for the spring action to press the gasket on the underside of the crown firmly against the lip of the tube, but not so much that there is any tube at all showing when the lever is engaged. I understand that this is the hardest part of the process because it requires very precise adjustment of the stem. The distance the tube sticks out from the case is of course determined by the sice of the crown's recess, but the force with which the gasket is compressed is dertimed by the lenth of the stem.

Of course the diameter of the part of the tube that sticks into the case is determined by the size of the hole drilled in the case. I know that it is 3.25 for Jimmyfzu cases, but smaller for standard rep cases if there is such a thing. Of course making the OEM crown work on a handwind movement requires either shaving off the threads from the stem and glueing it as some have done w/ zero problems or by removing the threads w/ a lathe and the rethreading the stem to .9mm as my smith does.

[dsp5500]

Interesting Archibald, Could you share some pictures of the work your guy has done? Or have you had any gen auto crowns installed on auto reps your self that you could share the results? I really would like to get this done to my 027/028

Rob