Re-casing an old school franken 36B

[w0lf]

Hiya,

As I was working on this beauty for a good forum pal, I snapped a few quick phone pics with his permission. The idea was to show that even a simple task like re-casing an old school franken build with better modern case parts needn't be a mindless exercise. It can be a bit more than loosening and then tightening six screws - every project, no matter how small, deserves a little bit of a caring touch to make it shine. I will leave it up to the owner to post good quality pics as I think phone pics should suffice for this one.

First up was the replacement case. As DSN cases come lacking any strap lip at all, if you mount even a regular thickness strap it will rub on the bottom edge of the case. So I normally cut in a brush a period-correct strap lip profile to mimic the gen case. Crystal install was straight forward so I'll skip it, DSN's gaskets are nice and thick, no surprises there.

The old school case that the watch came in had poor geometry among other inaccuracies. The gen bezel fitted on it was secured with cement and no gasket. It was a bit of challenge to get it off without bending. Rather than using a case knife, I taped the case up with polyamide and wedged single edged utility blades from opposite sides simultaneously to break the bond. In order to affix the bezel to the new DSN case, a more graceful method was used. Genuine bezel gaskets are impossible to find so I made a gasket by combining 5mil poly with a rep gasket, this gave me the right .56mm thickness and a nice and tight fit.

Here you see the final fit with the service gap facing 10 o'clock per OEM design.

Next up was the caseback. It is in fact the only good thing about the older rep, the caseback engraving and fonts are more accurate than DSN's caseback. What's not adequate for a timepiece of this magnitude is the tinny-tiny mineral glass display of the old caseback. Luckily, I had one of the old sapphire backs from a very old Eddie Lee rep. The crystal is not only thicker, but is also beveled, cleaner in appearance and gives the movement an extra bit of sharpness.

The screw ends need to be flattened so they're flush with the lug, a small detail that needn't be overlooked when working Ti cases other than H and N-Factory.

Lastly and I didn't take pics of this step, it seems trivial but don't underestimate the proper fastening of the movement inside the case, especially if it's a manual-winder. Always use the right size tabs and screws, I prefer the tall shanks and wide heads of ETA screws with correct 6497 wide and thick tabs. Rep screws are much shorter and flimsier, make half a wrong turn and you'll leave the screw shank in the mainplate. Rep screws are not any more accurate than ETA appearance-wise either because Panerai uses a cheese-head screw for clamping.

I don't have the time right now for a proper setup but I will leave you with a quickie, just to show-off the TST dial construction and patina in led light.

[projectologist]

Off the charts awesome work!  Well done.  I love this type of post.

Edited January 26, 2013 by projectologist

[omgiv]

Very talented and creative work. Good idea to use the tape to give you the right diameter.

[alnj]

nice.

[Cubeistan]

The thought put into this and workmanship are second to none. Beautiful job. Owner has to be jazzed.

[dluddy]

amazing work, as usual M

[Inertiadrifter]

I wish I have 5% of your skills W0LF Awesome

[Watchmeister]

Stunning work.

[tanya]

Magnificent work