timescreens

[CompuChron2]

Hi,
along with the P2 timescreen offered in the digital market place, i came accross crystals marked:
10-10 for one and H 980 for the other
any idea what they are for?
I guess the H980 is for Hamilton qed
see pics:

But the one marked S are unfinished...

[bruce wegmann]

Only Pulsar one is second from right. Others could be Novus or Wittnauer. Unfinished ones could be almost anything...

[CompuChron2]

Hi Bruce ,
you're probably right but they come from the firm or one of the firm which made them back then and here is what the guys who used to work there tells me:
"Yes, seed (the timescreen marked S)means that the edges have not been beveled and
polished to the final size. They are as supplied to Hamilton, who finished them in house or through the
use of local "jobbers".
The top right is a P4 NOS unsigned.
Interesting isn't it?But is it true?

[bruce wegmann]

Could be. Looking at the shapes, and allowing for rounding the corners. the end ones could be P4 or Dress crystals, and the center one could be for a Big Time. The rectangular one could be made to fit a Hamilton QED or Pulsar Calculator. There's a lot we don't know about how crystalmaking was handled for these watches, beyond the fact that the glass itself was from Corning.

[CompuChron2]

Easy question:
Timescreens on P2 and on date II are the same ,right?
Olivier

[bruce wegmann]

Identical size and shape crystals are used on the P2, Date II, P3, Classic, and PRM models. Some Classics and PRMs have laminated synthetic sapphire timescreens, but they are dimensionally the same.