Sandwich dials - How are gens cut?

[Rocketeer]

I've been playing at doing some sandwich dials and I've hit one problem I'd appreciate help with.
I've tried cnc milling and was reasonably happy, and was considering whether laser or water jet cutting would give a cleaner finish, when I chanced on this picture ('borrowed' from Watchprosite)

To me this looks more like a stamped cut-out, with the slight curvature to the edges that leaves, so, is this typical? Is this just from the surface coating process? or is this just another example of Panerai changing things just to be difficult? :twisted:

Anyone know how gen dials are actually cut?

 

[brtelec]

I do not know much about PAM production methods, but that dial in the picture is definitely punched out.

 

[rbj69]

HI, i personally bellieve they are machined ,, i have had about oh i would say 30 or 40 gens in my hand this year and i have looked at them pretty carefully and they all has a smmooth cut finish imo

joe(rbj69)

 

[babola]

Pam sandwich dials are made of two layers, bottom brass dics with shallow and wide engaving to make a wide and deep enough bed for lume application of correct thickness, and the top one which has been perforated at hour and indices places to show the lume applied at the bottom layer.

Not exactly something you'd call a complex dial production these days...yet the replacement dial thru Panerai service centre would set you back a small fortune these days, if you could source one that is.

babola.

P.S. Panerai don't 'punch' their dials, sure the pic above looks like that, but that's only an optical illusion.

 

[konigwolf]

The cheapest and easiest way would be cold stamping and if the punches where hardened they wouldnt leave a deformed edge but you can also machine them, but with metal that thin youd have to hit over 15000 rpm something like a gravograph machine would do it, a laser engraver would be the only other way but they only remove microns at each pass so it would take a good few hundred passes, Im sure Paneria will find the most elaborate and expensive way to do it. but Id go with stamping its the only way to repeat constantly the same design.

 

[rbj69]

HI, just to make sure some dont get confused , some pam dials are not two parts some are one piece and machined out and looks sandwich and the filled with lume , i have seen more of these than i have two parts in genuine , i guess they do it many different ways in genuine just like reps, lol

joe(rbj69)

 

[hooligan]

Actually, if you include modern sandwich, modern contemporary painted and then sausage dials (A-D series, plus current 000 and 005), there are really 3 different types of dial construction...

 

[Rocketeer]

Thanks guys. I didn't want to put time into following a wrong path

cnc milling something like this is typically done with a 22,000 rpm cutter and I've found that a double pass gives me the best results with top plates of the right thickness.
Water jet cutting is fast and clean but the people that do my laser-cut stencils handle everything from fine engraving through to cutting computer chassis, so I'll be interested in seeing how good a job they can do.

Next problem is deciding an ideal thickness for the dial, there seems to be a huge variety out there :evil:

 

[Jurgenk]

That first picture is really interesting. It does look like its stamped out, or deformed, but I think that it's actually just rounded off on the edges.

For what its worth, the latest DSN dial came to me with the same rounded edges evident on the top layer of the sandwich, particularly on the cut out 6 numeral.

It's actually not deformed, but looks like the dial was blasted with something to smooth the rough edges after being cut. Is it possible that he actually PVD's the top layer after some bead blasting? Is it possible that that radiomir sandwich gen went through the same thing?

In any case, I'm glad to see a radiomir gen with that same look to it, it makes me feel better about the DSN and tells me what he must have been thinking in this latest V 6.0 dial, or whatever version we're up to. It's not a bad dial in other respects, either.

 

[babola]

You're spot on J,
DSN dial makers use slightly different production techniques from the standard Pam rep dial makers and closer to the genuine Pam dial production, you only need to compare the two rep dials side by side (granted you need at least 4X loupe) to notice the differences and fine detail associated with DSN dials...if we could only get those dials look closer to their gen counterparts, DSN would be selling truckloads more :wink: ...but we're slowly getting there 8)