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Removing any scratch from your acrylic crystal

  1. Swissmister

    Swissmister May 24, 2019

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    We all encounter badly scratched crystals from time to time, and in some cases it is best to replace a badly damaged crystal, but in my experience, if it's not cracked or crazed (scads of tiny crack-like lines) it can be saved. So if you have a watch with a crystal that is difficult to replace and/or difficult to find, here are some tips for bringing back a badly scarred crystal (or not-so-badly scarred).

    1. For light scratches, (the kind you cannot feel when you run your fingernail over them) the usual polishes will do the trick. I know many love poly watch, but I find it unnecessarily expensive. I recommend Novus plastic polishes instead. These come in 3 "grits." I find number 2 is great for light scratches and never really found a need for number 1, a super fine finishing polish. And yes, toothpaste will work on the lightest of scratches.

    2. Now, of course, any polish will work if you are willing to spend hours polishing, but most of us would prefer to get on with our lives. For scratches that are a bit deeper, the kind you can feel with the edge of a fingernail, more aggressive measures are needed. My next choice is the scotch-brite ultra fine pad. I know, it is meant for metal polishing, as are a few of the products I will suggest. At this, already some of you are thinking, "This guy has been wearing Endura watches too long." It may seem counter-intuitive, but sometimes one must create more scratching in order to remove deeper scratches. This method will remove all but the deepest scratches. Cut a small piece and polish the scratched area until it appears the offending scratch is gone. Yes, you have created a larger ugly area now, but trust me, it's ok. At this point you have options. I have used liquid brasso (smells AWFUL) to do this rough polishing. More recently I have tried cape cod cloth with great success as an intermediary polish. You could even go to Novus number 3 (heavy scratch polish) at this point, but I'd save that for the next step. I know, Brasso and Cape Cod are metal polishes. They work. Much of my plastic polishing has been done on vintage turntable dustcovers, and Brasso has done very well as an in-between step. Now you should have your work area down to light and very light scratches. Now use the Novus number 3 if you have it. It will save time rather than polishing for 30 mins with a lighter polish like Novus 2 or Polywatch. After a few minutes with Novus 3, you should be ready for final polishing with Novus 2, 1 or Polywatch (even toothpaste).

    3. I recently received a watch that had been abused, and some of the scratches were very deep, more like gouges in some cases. These may be so deep that you can easily feel them by running your finger over them. These would require many hours of hard work with liquid polish, and even with scotch brite they would be exhausting. This is when sandpaper is needed. Yes, sandpaper. The more squeamish among you may flee at this point. I understand. It may be that the gouge is too deep and would require the removal of too much material. In that case, you will need to replace the crystal, but in most cases, you can remove the damage. I will include a couple of before and afters from the most recent project. It had 3 or 4 very deep gouges. DO NOT use heavy grit sandpaper. I recommend 800 or 1000 grit. If the crystal needs more than that, it is likely finished. Fold your paper down to a size that is manageable for small areas, (and you may want to use masking tape on the nearby metal surfaces, which is not a bad idea when doing any polishing of the crystal) and begin sanding the deep scratches. You will begin to see progress and material being removed. Do not be too aggressive. Use only enough pressure to do the job. When you think the scratch is gone, proceed with step 2 above beginning with scotch brite and on to the polishing. From time to time, examine the area with magnification. You may find you did not remove the deepest part of the scratch. Go back with the sandpaper and remove a bit more then on to step 2.

    Using this method, nearly any scratch/gouge can be removed. It might be wise to experiment on a lesser watch until you feel comfortable. Below are a few photos showing the products and the before and after of the crystal I recently "sanded."
    wak before.jpg A6F4A8BD-E6BA-4697-A1E0-A9F509B8E180.jpeg C409CB2B-3103-444F-9709-B77C241E7526.jpeg
     
    Edited May 24, 2019
  2. Wuza72

    Wuza72 May 24, 2019

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    I like it, go on, waiting for more Pictures :thumbsup:

    Trying to find these products in europe could be a challenge, but i´ll try.
     
  3. Professor

    Professor May 25, 2019

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    I use a plastic fingernail sanding board with four surfaces, two on each side. Only two of these surfaces are suited to acrylic watch crystals.
    There's a light blue and a white emery surface.
    I use the blue to go down past the deepest scratches then use the white to do a fair starting polish. At that point its nearly good enough and serviceable , but I then use a automotive plastic lens polishing liquid to bring it to a sparkling clear finish.
    All polishing is by hand.
     
  4. Swissmister

    Swissmister May 25, 2019

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    There is a great product made to polish plastic rear windows in convertibles that I used years ago for my cars and watches. The emory boards you describe would be the same as fine sandpaper. There are other materials that can be used effectively. I was passing along what I had learned from experience. Any other products and techniques are welcome. More options is a good thing.
     
  5. jimmyd13

    jimmyd13 May 25, 2019

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    I should take some photos of the next badly marked glass I polish (but then there are plenty online already).

    Deep scratches I tackle in stages: emery cloth; 1500 grit; 2500 grit; then polywatch (or toothpaste). By the time you're down to 2500 grit, the glass will look like it's completely fogged over but it only takes a minute with polymath to bring back to shiny.

    Actual glass glasses are a different story - break out the dremel; diamond paste; Jeweller's rouge. BE VERY VERY VERY CAREFUL. Ideally remove the glass.
     
    Kapka likes this.
  6. Archer

    Archer Omega Qualified Watchmaker May 25, 2019

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    An example of removing some deep scratches...initial condition:

    [​IMG]

    I start out quite aggressive, but I have a lot of experience at this, so for the amateurs out there you might want to go finer and slower:

    [​IMG]

    [​IMG]

    All polishing is the same - remove all scratches of one grit before moving to the next. If you move on too soon, you will have to back up a step in the process. I try to make the steps between each grit small, but clearly visible as I'm working. In the end the results can be very good if you have material to work with:

    [​IMG]

    [​IMG]

    Cheers, Al
     
  7. Swissmister

    Swissmister May 25, 2019

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    That sanding block (I used these for rough drywall work) would be the equivalent of course sandpaper to start, and if the crystal were very deeply scarred, it might be fastest and most efficient, as long as you bring it along one step at a time, following the course sandpaper with finer grit as you noted. Your note about removing scratches at level before moving to the next is dead on. There are definitely many ways to skin these cats.
     
  8. Screwbacks

    Screwbacks May 25, 2019

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  9. Swissmister

    Swissmister May 27, 2019

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    That would come in handy handy at times but must be sure to protect your bezel or remove it. Many good bezels have become "ghost" bezels from polishing the crystal and bezel at once.
     
  10. axl911

    axl911 May 28, 2019

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    Hmmm. Let me get my dremmel out!
     
  11. sirish19

    sirish19 Dec 3, 2019

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    Thanks for the post. I recently took a little tumble and found that I had scratched my Hesalite crystal on my beloved Speedy. I called Omega as well as an independent that did the service for me previously and Omega said it would be at least $250 to replace the crystal only and the other place required an overhaul before they would replace the plastic.

    I tried for about 30 min with polywatch and got it cleaned up to this point, but still noticeable scratches. Is this salvageable and what are the recommendations to start? I can still feel some of the scratches with my finger. Should I start with fine sandpaper or should I start with scotch brite?
     
    IMG_0569.JPG IMG_0570.JPG
  12. 03Hemi

    03Hemi Dec 3, 2019

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    You have to sand them out with various degrees of wet/dry sandpaper and then polish at the end. Your just polishing the scratches.
    Like Archer posted, it'll become hazy and opaque before it gets clear again.
     
  13. Martin_F

    Martin_F Dec 3, 2019

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    Make sure you protect that bezel whatever you do. Especially if you're working face down.
    Would be a bad surprise if you found that you've also sanded the numbers off your bezel!
     
  14. absoluteczech

    absoluteczech Dec 3, 2019

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    if your finger nails catch the scratch then no amount of poly will work. it will require sanding/wet sanding until its even, then polishing it back up. As others mention if you decide to do that, protect the bezel.