Once I took the watch apart, I couldn’t help myself but to work on the crystal. I did some research and find out that the Seiko branded Hardlex Crystal is somewhere around 7 on the hardness scale from 0 to 10. I also find out that it is possible to remove scratches with a few different levels of sand paper. First I started with a thicker grit of 800 until the deeper scratches disappeared. That initial process was taking quite a long time so I moved down a bit and tried 400 grit. Then I move on to a very fine grit but it did take some time to polish it nicely. Take a look at a few images I took before, during and after the process…
I have no idea what they did with the watch, but it took me more than an hour to get rid of all the deep scratches. I was thinking about using a Dremel tool to speed up polishing… but apparently when Hardlex heats up, it gets foggy. It is better to use the sandpaper with a bit of water even if it takes longer.
The final result isn’t as nice as I would like it to be but it’s a step forward. I couldn’t find sandpaper of more than 1000 and had to stop. Ideally, the deeper scratches can be removed with 400-800 grit, lighter with 2500 and final touches should be done with 5000. It is hard to find 5000 sandpaper at a normal hardware store so to wrap up the project I will have to order it online.
Yes, I know that the time spent on sanding down the crystal could have been spent on finding a replacement crystal on eBay. I wanted to see if the process works the result it produces is acceptable. Any advices?