My PO have some scratch. I think the scratches is on the AR coating. I have tried to use polywatch, but it doesnt help..

Some ideas to fix it?

 

I believe that AR coatings are only applied to the inside of the watch crystal. If this is the case, then the scratches you are seeing are not to the coating, but to the sapphire itself. Sapphire is incredibly hard to scratch (bravo for finding a way to scratch it), but that also means it is equally as hard to polish.

You will have to polish this crystal with diamond paste, and a good deal of patience. Otherwise, replacing the crystal may be a better option.

 

I owned the same type watch years ago. I had same issues. I polished off AR coating with Polywatch, and it took a great amount of time and effort. I believe there should be a post/thread on this topic, specifically for PO.

 

No - many are coated both sides. For removing outer AR coating I use diamond paste - fine so 0.5 or 1 micron will do the job with just dabbing a bit on the crystal and rubbing it with your finger.



The scratches shown by the OP appear to be in the AR to me...

 

Was it like my watch with discoloring? And how many minutes should İ use polywatch? I polish with finger in few minutes, and i think it doesnt be better.

 

İt's the glass, and should be ar coated both side

 

D

Do you think the polishing will help?

 

Why do they coat the outside if it is prone to scratching like that? Is it because doing just the inside does not do the trick?

 

Yes.

Because it reduces glare more if you do both sides.

 

It looked very similar to your watch. It took me about 45-60 minutes and I was rubbing the crystal using polywatch really hard using the cloth that came with the polywatch. Would never rub it that hard on a hesalite.

I tried to search OF, but found nothing. I think I must have posted over at WUS, back when I use to post there.

 

My PO is double coated too. Many watches are, it’s a silly design really since the coating is nowhere near as hard as the underlying sapphire. If you are going to use something stronger than Polywatch, and why wouldn’t you, life’s too short, then take care and maybe mask the bezel.

 

Then I have to try later today. But where can i buy diamond paste? And wich color should İ use? And can İ scratch the sapphire glass with polishing?

 

Then İ will try but it will take too long time

 

What should İ use?

 

Anything mildly abrasive will work. Even toothpaste perhaps but proper diamond paste is available from eBay and jewellery supplies vendors. Diamond paste could scratch the crystal if you applied it with a Dremel or extreme force but as Archer suggests use finger pressure and all will be well. I have had limited success in improving scratches in actual sapphire using diamond paste but it takes a very long time to effect the underlying sapphire.

Polywatch sell a kit for polishing scratches out of mineral glass that includes a small amount of fine diamond paste, this will to a certain degree work on scratched sapphire too. It would certainly remove AR pretty quickly.

 

Wonderful information thank you.

Does taking the AR coating off in the way you mentioned invalidate the warranty?

 

This Q is often asked in photog circles. Roger Cicala, owner of lensrentals.com, wrote something on it. (He also likes to play with lasers and did a fairly comprehensive test on light transmittance from protective lens filters.) In general, about 4% of light is reflected from each side of uncoated glass. So, even if you have one side coated, the uncoated side will probably negate some of the effects of the coating. For a truly clear AR effect, both sides should be coated.

 

No, it shouldn’t.

 

I will never understand why a 'tool watch' requires AR coating on the outside of the sapphire crystal. Kinda voids the whole purpose of using sapphire to being with i.e. being really hard to scratch.

 

The PO (and similar) stopped being tool watches decades ago.