Understanding the Pierce Waterproof Case

[RyMoeller]

If anyone has happened to work on a Pierce chronograph with a waterproof case, I could use a little help.

I'm in the middle of another Pierce chronograph restoration and this is the first I've had with a waterproof case.  The case is missing the pusher buttons and stem tube, but I can see that the holes for all three are threaded. The holes for the pusher tubes have a small red rubber gasket inside and behind it there appears to be a compression spring. The hole for the stem also has a rubber gasket which is secured with a threaded ring.

This is the first time I've encountered a waterproof case by Pierce and I'd like to return the watch to as close as possible the original specifications. The problem is that I don't have the pushers or stem and I do not understand how they were engineered. Naturally I can fit off the shelf replacements but I would like that to be Plan B.

If anyone has any prior experience with Pierce's odd case please feel free to chime in. They had odd solutions to many challenges an I'm interested in finding out how they made their waterproof chronograph.

[matabog]

My only understanding of Pierce chronographs is from your walkrhroughs

[clockboy]

Found this on another forum which might help:There is actually quit a bit on the net about the Pierce including a vid (not your calibre) 

 

http://forums.watchuseek.com/f11/pierce-chronographs-401881.html