OMTech M30 MOPA Fiber Laser: Setup, LightBurn and Settings

The OMTech M30 was my first fiber laser. It's a 30W MOPA fiber galvo, and fiber lasers are really good at marking metals, slate and plastics. A MOPA source also lets you control the pulse, which is how you get color on stainless steel.

OMTech sent me this one, but they had no say in the video. Here's how I set it up, how I focus it, how I got it working in LightBurn, and the exact settings I used on every test material.

Jump to: What you get · Connecting it up · Powering on · Focusing · LightBurn setup · My settings · Pros and cons

What you get

The laser comes in two parts:

• The control unit. About the size of a PC, with self-retracting handles, an emergency stop, a green reset button and a key switch for the scan head. It's heavy and feels very industrial, which I like. It's also surprisingly quiet, so it can sit under the desk.
• The galvo head on a Z axis column, with a crank on top to raise and lower it by hand, and a base plate with M6 threaded holes for clamping your work down.

The two are joined by a long cable that comes already attached. In the box you also get safety glasses, a toolbox with screws, Allen keys and a tape measure, a ruler, L-shaped brackets for holding parts down, and a USB stick with the software files.

Mine also came with an enclosure that makes it a Class 1 laser. It has a door, a fan, an LED halo light and limit switches on the door, so the laser shuts off if you open it. If you're putting this in a shared space, that's a good layer of safety, because fiber lasers can damage your eyes.

The advertised specs are a JPT 30W MOPA source, a 175 x 175 mm (about 6.9 x 6.9 in) working area with the standard lens, up to 7,000 mm/s, and LightBurn compatibility.

Connecting it up

The column comes off the base, so the first job is attaching it with four screws. That was easy enough, though an extra pair of hands helped. Then the cables:

1. Power cable. It only goes in one way (three pins). Push it all the way in, then tighten the threaded collar so it can't fall out mid job. Mine came with a UK and a European lead, so check you've got the right plug for your country.
2. Enclosure cable into the Protective Cover port, held with the two screws either side. This powers the enclosure's light and fan, and carries the door switches. It has to be plugged in to run the laser.
3. USB from the back of the unit to your computer.
4. Optional: the foot pedal and rotary have their own ports, and there's an earth point at the bottom if you want to earth the machine.

Put the control unit somewhere you can reach the emergency stop easily.

Powering on

Before anything else, take the cap off the lens. I forgot, and melted the top of mine a little. Learn from my mistake.

1. Make sure the emergency stop isn't pressed in. Mine was.
2. Turn the scan head key.
3. Press the button on the control panel to start it up. You'll hear the fans power up, then your computer will connect to it.

Focusing it

This laser has no autofocus. You focus it by winding the head up or down with the crank on top, and there's a scale down the column to help. My lens is the 175 one, and the label on the head says its focus distance is 363 mm.

There's a focus switch on top of the head. Press it and two red dots appear. As you raise and lower the head the dots move closer together or further apart, and when they meet, you're in focus. That relies on the two little lights being in the right position, though. Mine were, but if they get knocked you can't fully trust them, so double check with a measurement.

I started off using the ruler that comes with it, measuring from the bed to the red mark on the head. Then I printed a galvo focus stick from MakerWorld (not my design, but a great one). You set it to your height and it slots on, so you get the same distance every time. It sped things up a lot.

Setting it up in LightBurn

1. On the USB stick that came with the laser, open the Software folder, then the plug folder. Find the file called markcfg7. Remember where it is.
2. In LightBurn, click Find my laser. Mine found it straight away. If yours doesn't, you may have to add it manually.
3. When it asks, import the markcfg7 file. It holds the settings that are specific to your galvo, and LightBurn fills them in for you.
4. Click Next. Rename the laser if you like, set the units to mm per second (recommended), and check the bed size, which it sets automatically.
5. Click finish and you're ready to go.

My settings for each material

These are the exact settings shown on screen in the video. They're a starting point, not a guarantee, so run a test on a scrap of your own material first. Pulse is the same 200 on every one.

Metals

The spanner shows how practical this is for marking tools. I tried a few settings on the back first and settled on these. It's indelible, and I think it could go even darker.

The 0.45 mm black anodized aluminum business cards came out really clear.

The stainless steel tag was one of my favorites. It's hard to explain just how pure a black that is.

Leather, slate and 3D prints

On the tan PU leather the contrast is really black. On a black PU keychain there's no contrast, but it still gives a nice 3D looking finish.

It did a brilliant job on 3D prints. I ran a material test grid on black PLA and black ABS first (30 kHz, 505 lines per inch, power and speed varied). ABS came out a bit darker, and I think you could get brighter results with more testing. I took the PLA settings from the grid and engraved the design above.

Color on stainless steel

This is where MOPA comes in. On a 2 mm stainless plate I ran a test grid at 60% power, 850 mm/s, 12700 lines per inch, with the frequency changing down one side and the pulse changing along the other. Each square comes out a different color. I've only scratched the surface so far, but there's a lot of potential here.

Cutting a business card

I also cut a star out of a 0.45 mm anodized aluminum card: 95% power, 500 mm/s, 40 kHz, wobble step 0.03 and wobble size 0.05, with the passes set high and stopped by hand once it was through. It took a few passes but gave a clean cut with a shiny edge. It did warp the card a bit, so those settings need refining.

If you've got an xTool machine, my free Laser Settings Library has hundreds more tested settings, including the F2 and F1 Ultra.

Pros, cons and who it's for

What I liked:

• It's heavy duty and solid, with machined metal parts. Made to last in a workshop or professional setting.
• The enclosure, if you want that extra safety, with its built-in door switches.
• A JPT laser source, from one of the well known manufacturers, and it's been reliable the whole time I've used it.
• 30W MOPA: color on stainless, quick metal marking, tool marking and more.

What could be better:

• The enclosure's door switches have to be closed for the laser to run, even if you just want to look in, position your item or frame it. I ran mine outside the enclosure, wearing laser safety glasses at all times in a locked room. If you do the same, make sure your glasses are rated for the fiber laser's 1064 nm wavelength, and keep everyone else out of the room while it runs. An official way to work with the door open would help.
• The instruction manual. It was enough to get started, but it isn't very thorough and the pictures aren't clear. I relied on my own experience, so a complete beginner might find it hard.

I think it's best for professional and industrial use, where you're marking things over and over, or for home use if you've got the space. Overall, I'd recommend it.

Questions about fiber lasers?

Ask in the comments on the video, and let me know what you'd like to see me try on it next.