The watch has a pressure fitted back, which was quite a pain to remove. I ended up scuffing the caseback, but was able to polish out the scratches using some Cape Cod cloths. Kapton tape is excellent for masking off parts you don't want polished (like brushed surfaces), and can be obtained for cheap from Dealextreme (search for "high temperature tape").
It had a 29.2mm flat sapphire crystal (measured using digital calipers) installed with crystal glue, which I was able to remove with a crystal press (from Harbor Freight Tools). I ordered a 29.2mm domed sapphire crystal by SternKreuz (from TwinCitySupply), and some UV crystal glue. Most domed sapphire crystals are only available in 0.5mm increments, except for the one from SternKreuz, but TWC only had one in stock, so I'll only be able to do this mod on one of my 3520D replicas. Anyhow, this is the 3520D in its component pieces.



The original residue from the old crystal glue was scrapped off, and I cleaned the surfaces using some rubbing alcohol. The domed crystal fell right in, and I applied the UV crystal glue using the syringe the glue came with, and it has the consistency of water. In any case, I applied a generous (perhaps too generous) amount in the small gap between the bezel and the crystal, and cleaned up the excess using an alcohol swab. The crystal glue was then cured under a UV lamp, and the excess glue was again cleaned off with more rubbing alcohol.
And now for some shorts of the watch with the domed crystal.


These are some side by side photos of the replica 3520D with the original flat sapphire crystal (left), and the new domed crystal (right).



Side view of the flat crystal.

Side view of the domed crystal.

Finally, this is a photo of a gen 3520D.

and some additional photos of gen Pateks, notice that the reflections suggest that the crystals are domed.


Edited by calatrava, 22 February 2012 - 08:14 AM.









