How to Replace Watch Glass (Crystal)
If you’re like me, you probably bang your watch crystal against different objects all day long. Even if you’re extremely cautious with your wrist movements, you will probably end up scratching your watch against something someday.
Hopefully, your watch will remain intact. Unfortunately, sometimes, the watch crystal can get severely cracked, or even break. When this happens to your favorite watch, you have no choice but to replace its crystal. This is why we’re here.
Removing the case
Before thinking about removing the glass, we first need to get to it. For this, you will need to remove the back of the case. There are several types of watch cases, so we will list the most common types and how to remove them.
1. Snap off
If the back of your watch is smooth without any screws or notches, it probably is a snap off case. Additionally, you can look for a small indentation on the side of the back. Often you will need a magnifying glass to see this indentation.
You will need either a bench knife or a case knife. You will slip the tip of the knife in the indentation to pop it open. This step can be dangerous both for your watch and your personal health. You will need to use a lot of caution not to let the knife slip.
source: Esslinger and company
Now that you have removed the back of the case, you can carefully place the mechanism of the watch somewhere safe where it won't get dirty or damaged.
2. Screw off
A screw off watch case can be recognized by the regularly placed notch on the back of the watch, as seen in the picture below. A couple of watches that use this case back are the Seiko SNK809, Orient Bambino, and many more.
To remove this type of case, you can use one of the three following tools.
Ball case opener
Any of these tools can be used to remove a screw off watch case. Each tool has its advantages and inconveniences. No matter which one you choose, we recommend also using a watch case holder, to help maintain the watch in place, avoiding any possible damages. The case holder is not mandatory. Take a look at the image below if you're not familiar with watch case holders.
source: Esslinger and company
The Jaxa Wrench is the most expensive tool on this list, but it is the one that works the best. You're better off using this tool if your watch is old and a lot of grime has built into it.
If you have a case holder, you will need to secure the watch in a position where it won't move. If you don't have one, you will need to put your watch on a soft surface such as a blanket. This will allow you to hold your watch in place without scratching the crystal on the surface.
The Jaxa wrench will come with a set of tips of different sizes. You can try different tips by hand to see which one fits you're case notches the best. You can then place these tips into the Jaxa wrench, most will have 3 tips. You will now adjust the wrench in order to get the tips to fit with the pattern of your notches. When your tips are inside the notches, you can gently unscrew the watch back. Once that's done, you can remove the watch mechanism and place it somewhere safe.
Explaining how to use a Jaxa wrench is difficult using text only, so we strongly suggest you watch the video below to help you with the task. You can also watch the videos for the ball case opener and the Case wrench if you'd rather use those tools.
3. Four Screws
The 4 screws case back is probably the easiest to remove. You will only need a small screw driver. You can loosen the screw as you would with any other normal screw. Once you removed all 4 screws, you will be able to lift the plate. To put it back on, you can simply put the back in place and screw the bolts back in.
This type of case back is very popular with digital watches, like the Casio G-Shock.
Removing the crystal
What you will need:
A watch press is an inexpensive tool that is used to press the crystal out of the watch case as easily as possible. You can get one online from 15-25$ depending on the quality. Usually, the press will come with a plastic die set of different sizes to help you remove the crystal from any watch.
First of all, you will need to choose two plastic dies out of your set. The first one will be as big, or a little bigger than your watch case (see first picture). It is important for this die to be concave (center is deeper than the rim), as it will receive your watch crystal. The second die should be just a bit smaller than your crystal, as seen in the second picture.
You will now place the two dies in your watch press. The smaller die will go in the top section, to press in the crystal. The bigger die will go on the bottom, with the concave side facing up, to receive the crystal. You will then place the watch case in the press, with the glass facing down, laying on the big die.
You can now gently apply pressure on the press to get the crystal out. As seen in the first picture, you can use your left hand to keep the press stable, and your right hand to apply light pressure. The crystal should slide right off, as seen in the second picture.
Your crystal is finally out! You can now take measurements of the diameter and thickness to order the right replacement crystal. Most watch nowadays come from the factory with a mineral glass. If that's the case with yours, we strongly suggest you replace your mineral glass with a sapphire glass. Sapphire is extremely resistant, and can basically only be scratched by diamond or sand.
Once you receive your new crystal, you will evidently need to put it back on. This time, we will use a die that fits inside the case for the bottom of the press, as seen in the first picture. Instead of using a concave die, you will need to use a full (flat) die this time. For the top of the press, you can keep the same die you used to remove the crystal.
You will now place the watch case with the bezel facing up, as seen in the second picture. You then need to put the new crystal inside the bezel. After that, the only remaining step is to press down gently, until the crystal is firmly inserted inside the case.
The final step is to place the mechanism of the watch back in, and to place the back of the case on. If you have a snap off back, you can simply snap it back on using your fingers. If this doesn't work, you can use the watch press to put it back on.
If you have a screw off back, simply go back to the videos posted in the first section of this articles, as they explain how to screw it back on.
We really hope this tutorial helped you to change your watch crystal. If a step of the process isn't clear enough, please leave a comment so we can address the issue and clarify the step. Thank you for reading!