How to repair the clamp crown on the original Airman by Geoff Quickfall
originally posted at WatchUseek unofficial Glycine forum 22-03-2005

I have had 3 requests for explanations or help getting the clamp crown on the original airman restored. I saw recently an Ebay listing, also with the clamp crown stem assembly missing.
So here is a cross section view of the assembly that I used to explain the mechanism to a case repair specialist based in Florida (my thoughts on it, I don't have access to the original diagrams). I will include his link at the end of this posting.

In my case (pun intended) the clamp was missing and the clamp post as well as the clamp stem was filed flush to the case. If these are only missing, ie, two holes in the side of the case it probably means that the retaining pin under the bezel has corroded or sheared allowing the clamp crown, stem and subsequently the clamp to be lost.

So here goes the explanation (refer to the diagram done by my 20 year old cat (okay, done by me)):

1. clamp crown.(any correctly sized crown will do)
2. clamp crown stem.(any thicker than normal stem will do for strength)
3. lathed groove on clamp crown stem.
4. clamp crown retaining pin.(inserted vertically under the bezel)
5. clamp. (NOS from M. Seigrest if he still has some otherwise it will have to fabricated, I don't know why a new clamp from a similar sized remake wouldn't work, I don't know the dimensions)
6. movable 24 hr bezel.
7. watch case.

Not seen is the clamp post which stops the clamp from turning from the horizontal with relation to the case. It is located beside the crown, (see photo). Easy job to insert new pin, pressed in and filed flush to the clamp. If it has been filed flush to the case then drill out and insert new tapered pin. Of course a non moving case clamp and lathe with tap will be required.

If the clamp crown stem has been filed flush to the case as in my watch then a new stem hole will have to be tapped and dyed (rethreaded) to accept the new clamp crown stem.

I think the diagram is self-explanatory with the possible exception of the clamp crown retaining pin. This pin is located under the bezel (snap on and off). It proceeds vertically down through the case to meet the clamp crown stem. It sits in the groove creating limited movement to the stem preventing the stem from unscrewing. I guess you could create a threaded pin and threaded hole (too fancy) which would allow the entire mechanism to be repaired easily.

Any questions????

Cheers, Geoff (happy restoring)

originally posted at WatchUseek unofficial Glycine forum 22-03-2005