Friday, June 26, 2020

Case polishing explained

Last week we published a photo of before and after of a Rolex case polishing job undertaken by Bobby, second year apprentice.
The polishing was done by hand using just various grades of emery paper and a wooden stick, with mirror finish achieved on a rotating buff wheel (cotton disc and polishing medium).
The end result speaks for itself. We posted the photos on Instagram inviting our followers to rate the job anywhere between 6 and 9 out of 10. As we expected, almost all marked the job with top grade.  What we didn't expect: this photo was one of the three most liked posts with over 600 likes.

Yet a couple of watch enthusiasts couldn't help but to offer rather strange opinions on the matter. There were two complaints:
1. Case polishing is bad because it removes patina
2. Hand polishing and especially buffing on the wheel is a 'bad' method. Watch cases should be lapped, not polished.
Yes, for some, case polishing is a controversial issue.  Allow me to defuse it for you and help you understand the fundamentals.
Once you understand those fundamentals then you will be able to make an educated decision.

What is patina?
Patina is a green or brown film on the surface of bronze or similar metals, produced by oxidation over a long period. Patina is also a gloss or sheen on a surface of antique furniture resulting from age or polishing.
Please note: we use same term to describe completely different effects created in different manner on two different surfaces: bronze and wood. Yet in both cases, it is the patina - whether it is the sign of natural ageing, polishing with shellac and oxidation- which gives an object the distinctive 'naturally aged' shine and colour.
It takes no expert to appreciate that a fine bronze sculpture should not be polished (only dusted!), neither should a fine French polished antique table be stripped down to bare wood or attacked with aggressive polishing agents. We leave bronze and wood alone- to age naturally.
Stainless steel which is used in modern watches is a different story altogether. Ideally, stainless steel does not oxidize - so it cannot develop any patina whatsoever. The oxidation process of steel is simply called rust. Pitting is actually worse than surface rust - it is a nasty corrosion which kills the water resistance of watch cases. Since almost all modern watch cases are nowadays made of stainless steel, titanium or precious metal, we don't associate the term 'patina' with watch cases.  To use the term 'patina' on any watch case except bronze, is grossly inappropriate.

Stainless steel cases leave the watch factory with a variety of surfaces: polished, gloss, mirror finish, brushed, sand blasted. General expectations with modern watch servicing are to at least improve the condition of scratched cases, if not to return them to as close to original finish where possible. Again, not to preserve any patina - because there is no patina to be preserved.

"Please don't polish - I like my scratched case!"
Fair enough! If your wish is to have all the bruise marks, dents and scratches 'preserved' than who am I to argue with your choice? Indeed, some watch owners are very particular in this respect. However, it is important to point out the obvious:  a vast majority of MODERN watch owners would prefer polished cases and bracelets, restored it to 'like new condition'.  Scratches are bad and undesirable. Disagree? Would you intentionally scratch your new car? Or a brand-new laptop, mobile phone - or a brand-new watch? Removing scratches is DESIRABLE. It's good. It's fine. Removing scratches is difficult, and we don't do it just for fun or to impress you, so relax and enjoy your new polished surface!
However - there is an exception to this rule: unlike modern watches, rare, high value vintage watches SHOULD NOT BE POLISHED. Not because they are worth more when scratched, but because polishing - and in some cases even cleaning- could significantly reduce chances of assessing the originality of both external and internal parts. All the scratches, dings and dents help us to determinate if the watch is original or a Frankenstein put together from new and old parts, or a watch which has been restored correctly - or not.

Polishing is an inferior alternative to lapping
Yes, it is true that almost all modern stainless-steel watch cases and bracelets are polished with the help of modern multi-million-dollar CNC machinery, fully automated, in a process which no longer involves human touch. The final step of that polishing process is lapping. Lapping is a technique where a liquid polishing medium is applied between the work-piece (watch case) surface and a lapping plate. Due to the nature and geometry of those lapping plates, as well as highly controllable lapping action, this automated process produces very uniform surfaces which retain geometry. In other words, polished ‘edges’ are crisp, defined and 'sharp'. They look like they have been defined and polished by robots - which they are.
In other words, when it comes to case finishing, nothing beats machine lapping. Unfortunately, lapping is highly specialized process and your independent watchmaker is either not set for lapping, or when he is able to offer such service, it is only to a limited number of watch cases / shapes / brands. It is a trade in itself - and quite frankly, has nothing to do with watchmaking. To expect your independent small watchmaker to offer case refurbishment service equal to those of mega-brand is simply unrealistic: the same as expecting everyone to fly first class or drive a Ferrari.

"Oh NO! You've polished my watch and rounded the lug! I am devastated!!"
Unfortunately, we live in an imperfect world, and we have to put up with compromise. Watch polishing is ALWAYS a compromise. At the end of the day, you have to answer this question for yourself: which one would I prefer - "before" or "after"? Because this is all we can offer. Polished cases could mean some very minor 'rounding'. This is just a nature of the polishing process, especially when done by hand. However, an experienced polisher is well aware of the process and will do everything possible to keep the wheel buffing action just for the final mirror finish. When we remove scratches, we use a range of abrasive papers and films, in various grades, which takes a majority of polishing time and this is why our results are as per photo.
Not good enough for you? Well, the best polished case is - case replaced. For that, you need to talk to your watch brand service department. We can consistently offer; 6, 7 or 8 out of 10. On a good day - even a solid nine. For perfection see our competition.

There is no such thing as patina on steel cases. Scratches are bad, so take a good care of your watch and you won't need frequent polishing. Polishing is time consuming, requires skills- therefore expensive. Learn to live with small imperfections -life is not perfect. Be happy with the end result - returning the watch case to 'brand new condition' is impossible!

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