Polishing Acrylic Watch Crystals

WARNING: Do this at your own risk.

Vintage Timex watches have been around for a long time and in most cases are in average to poor condition. This is often heightened by having badly word scratched acrylic crystals that disturb your view of the dial.

In this tutorial i will guide you through my process of polishing watch crystals.

A lot of people use Polywatch which is a good but expensive way of polishing minor scuffs. For general use i prefer a more effective method. You will need:

Course nail buffing block
Fine nail buffing blocks
Glass polishing cloth
Liquid Brasso

Triage

Before you start i would check if the crystal is redeemable by removing it and checking for cracks or crackling. To do this hold the watch up to a light in various positions. Cracks show up as large solid white areas within the crystal, crackling looks like crazy paving. Polishing a crystal will remove scuffs and chips but a cracked crystal will need to be replaced. I would also give the edge of the crystal a good clean with hot soapy water to remove any debris that could be transferred onto the dial.

Here you can see a crack at the top of the case (yes i know the case is upside down lol)

I typically keep the crystal on the case for polishing as it allows for a better grip.

Timex Black Max with bloom and scratches on the crystal

Here we can see an area of bloom and some scratches. Unfortunately much of this issue was on the inside of the crystal meaning i had to use the approach on both sides. I rarely see this issue and mostly see it on these black max pieces

1. Course nail buffing block

Use the course side to give the crystal an evenly sanded finish

I use a general purpose nail buffing block that has 2 course sides. One being less course than the other.

Using small circular motions use the most course side to take off a good layer of acrylic crystal. The dial should get dusty and a lot of swarf should come off. At this point your dial will be unreadable through an even textured finish. Use the polishing cloth to wipe off the swarf and check for any gouges. Repeat if necessary.

2. Less course side

Use the less course side to make the crystal progressively smoother

Use the less course side of your nail buffing block to repeat the process. I find that wetting the block often delivers a better result.

3. Repeat using nail buffing block

I use a 4 grade nail buffing block and sand the crystal using all 4 grades. You can see the swarf here

The nail buffing blocks i use have 4 different sides each with progressively less grain. I go through each of the grains using the method outlined above until i have a clear crystal.

4. Liquid Brasso or Polywatch

use your finger to massage some Brasso onto the dial before polishing

Liquid Brasso is a thin paste used to clean brass and metal. It is also great at giving your crystal that high polished finish.

push down on the watch and use circular motions when polishing a watch crystal

Place your polishing cloth flat on a surface and put a small amount of Brasso onto the cloth. I usually use a finger tip to rub some of the Brasso onto the crystal just to make sure its covered. Now turning the watch head upside down rub the crystal onto the Brasso infused cloth, again moving in circular motions until you have given every facet of the crystal a good rub.

Now clean off the Brasso using a clean part of the glass polishing cloth, again giving all facets a good rub.

You should now have a crystal clean watch crystal.