Dobot Mooz is a 3-in-1 machine for 3D-printing, laser engraving and CNC carving. The MOOZ-2 Full version ships with a 0.5W laser by default. Since I wanted to be able to cut balsa wood and other materials easily, which is quite hard with the 0.5W laser, I decided to buy a stronger one. I chose a 2.3W laser from Banggood, but this tutorial should work the same for both, the 2.3W laser and 2.5W laser.

You just need a laser module for about 60$, 4 cables and a soldering iron. In the next step, I have attached links for buying these items.

Step 1: Buying the Laser

I ordered my laser on Banggood. It was about 60-70$, so it is not too expensive. You can generally order any laser you want, but you have to take care of a few things:

The connections. Mooz supplies the laser module with a 12V VCC pin, a ground pin, a 5 PWM (TTL+) pin and another ground pin. The laser requirements should state if these pins are supported. There are different types of laser modules: I found one that just has 3 pins because there is only 1 ground pin. That does not matter since you can simply leave 1 ground pin of Mooz's cable unconnected.
The size. The base size should be 33*33mm. The height of the laser I bought was 76mm and it fitted, but should not be higher than that.
Screw holes: In order to fix the laser, there should be holes on the bottom side, as marked in the image attached to this step.
The focus adjustment wheel's diameter should not exceed 20mm.

Here are 2 links of a 2.3W laser and a 2.5W laser that fulfills these requirements. I cannot guarantee that it is going to work with your Mooz, but you should be on the safe side if you choose one of these two:

2.3W Laser from Banggood

2.5W Laser from Banggood

If you choose a laser from Banggood (I checked many online shops and they were the cheapest), I advise you to check the different shipping options. I chose a shipping method that was just about 2$ more than the standard shipping but way faster.

You will also need 4 cables to connect the laser to the Mooz module. I simply used 4 male-to-female jumper cables, but you can generally use any isolated wires. Here is a link to jumper cables on banggood.

I have not tried it, but JST cables with a 2.54mm pitch should work for both, Mooz's and the laser's connector. You would need two 2-pin cables and a 4-pin cable. The advantage of the JST connectors is that you do not have to solder onto the laser's pins directly.

Step 2: Opening the Module and Removing the Old Laser

There are two hex keys included in your Mooz package. Remove the top cover of the laser module using the bigger one. Next, remove the bottom cover. Now, remove the two screws at the bottom of the module fixing the laser using the thinner hex key. Be careful not to wear out the screw heads. All of these 3 steps are illustrated in the images attached to this step. Finally, simply unplug the laser's cable and take it out of the module.

Step 3: Mounting the New Laser

In order to be able to fix the new laser with the 2 screws, you will probably have to create screw threads in the mounting holes of the laser (marked in the image) before putting the laser into the module. To do so, you need the two screws the old laser was fixed with. Screw them into two of the mounting holes very tightly (use the long side of the hex key) so that screw threads are milled into the aluminium. At first, I thought that was not possible, but you just have to apply much force and it will work.

After creating the screw threads, you can insert the laser into the module and fix it with the two screws, exactly like the old one. Make sure to tighten the screws so that the laser sticks well.

Step 4: Connecting the New Laser

Variant without soldering: In addition to the method described below, it is also possible to connect the laser without soldering. You need 2x 2-pin 2.5mm connector JST cables and 1x 4-pin 2.5mm connector JST cable. Plug them in and connect the 8 cables according to the picture. I have not tried this variant but it should work fine.

At first, create a 4-pin-plug in order to connect the 4 wires to the Mooz module. I did so by simply fixing the female ends of the jumper cables with tape, as seen in the first picture. Plug it into the plug on the green PCB board and fix it with some tape. If you have a JST connector, you do not need tape. I do not advise you to solder the cables onto the plug on the Mooz module in order to avoid troubles when changing the laser again in the future (no idea though why you would want to do that :-) ).

Now the most difficult part has to be done: soldering the wires onto the laser connectors. I removed the 2 white JST plugs with pliers so that the soldering is easier. If you have the FB-04 version of the laser, there are 5 pins (from top to bottom): VCC, GND, PWM, PWM, GND. You do not need the PWM pin in the middle. If you have the FB-03 version, you just need the top 3 pins: VCC, GND and PWM. I attached an image showing how to connect the cables to the FB-04 laser. If you have the FB-03 laser with just 3 pins, simply do not connect the orange cable. Solder the wires onto the pins. If you are using jumper wires, make sure that you do not solder the connectors of the cables onto the pins vertically, but horizontally (lying), as shown in the image. Otherwise, you will not be able to attach the top cover of the laser module. Be careful not to activate the white button on top of the laser accidentally.

As someone recommended in a review on Banggood, I added a 4.7K resistor between the upper GND pin and the PWM pin (as shown in the image), so that the laser is shut off by default (when just VCC and GND but no PWM cable is connected). That might be useful to prevent the laser from running at 100% power and potentially causing a fire if not surveilled when a cable becomes loose, but it is not necessary.

Step 5: Finishing

Now, you can add the top and bottom cover again. Mount the module on your Mooz plug the cable in. Never use the laser without protective glasses or without surveillance! I had to use the adjusting wheel on the bottom of the laser to lower the focal height so that the laser can be focused.

Thanks for your attention!