How to Set Up Your OMTech K40+ Laser Engraving Machine

OMTech Laser Updated On Apr 23, 2025

If you’re the proud new owner of an OMTech K40+ laser engraver, congratulations! You’re about to unlock a world of creative potential—engraving and cutting everything from wood and acrylic to leather and rubber. But before you start customizing coasters or crafting signs, you'll need to get your machine up and running.

The good news? Setup is easy. In this guide, we’ll walk you through each step to get your K40+ ready, based on OMTech’s official setup video. From unboxing and assembly to connecting your exhaust fan and firing up the machine, we’ve got you covered.

What Comes in the Box?

Your K40+ is thoughtfully packaged with everything needed to complete setup. Here’s what you’ll find when you unbox:

OMTech K40+ Laser Engraver
Power cord
USB cable
Exhaust fan and duct
Water pump
Tube of silicone sealant
Air assist nozzle and tubing
Tool kit and screws
User manual and documentation

Make sure all components are present before you begin. It’s also a great idea to clear a sturdy, level surface near ventilation—your workspace should be clean, dry, well-lit, and between 5 and 35 degrees Celsius.

Step-by-Step Guide to Set Up Your OMTech K40+

You can follow the guide below or watch the video guide at the end.

Step 1: Remove Packaging and Inspect Your Machine

Start by carefully unboxing your K40+ and removing all internal foam inserts, zip ties, and protective film. Check inside the machine bed, laser tube housing, and accessory compartments to ensure nothing is blocking moving parts.

Visually inspect the mirrors, lens, laser tube, and wiring for any signs of damage during transit. If everything looks good, you’re ready to assemble.

Step 2: Connect the Exhaust System

Proper ventilation is essential when operating a CO₂ laser. The K40+ comes with an external exhaust fan and flexible ducting to help direct fumes outside.

Here’s how to connect it:

Attach the duct to the rear exhaust port using the metal clamp provided.
Place the exhaust outlet near a window or an external vent to ensure safe fume expulsion.
Secure all connections tightly so there are no leaks.

Tip: You can upgrade this setup later with a more powerful filtration system for indoor use.

Step 3: Set Up Water Cooling

The K40+ uses a water-cooled laser tube, which must remain at a safe temperature during operation. The included submersible water pump helps circulate cooling water through the system.

Here’s how to set it up:

Fill a clean bucket with distilled water between 15 and 21 degrees Celsius only—tap water can damage the laser tube over time. Ensure there are at least 7.5 liters of water in the tank at all times.
Install the suction cups and outlet on the water pump, then connect the pre-installed blue hose on the machine to the water pump.
Submerge the pump in the bucket. Place the other hose in the bucket and make sure the return water flows smoothly into the bucket.
Plug the pump into a power outlet.
Turn it on and check for continuous water flow through the tube.

Tip: You should see water flowing smoothly through the clear tubing and no air bubbles larger than 1 cm in the line.

Step 4: Connect Air Assist

To help keep your engraving clean and your lens free of debris, the K40+ features an air assist.

Turn on the machine and release the emergency stop button. Make sure the laser head nozzle is spraying pressurized air.
Turn on the air assist during operation to blow smoke away from the engraving area.

This not only improves engraving quality but also prolongs the life of your lens.

Step 5: Check the Safety Features

Now that all physical systems are assembled, it’s time to ensure your machine’s safety settings are functional:

Turn on the key switch, press the reset button, and press the emergency stop. The entire machine should power down, meaning the emergency stop button is working.
Moving forward, turn on the water pump. Close the cover, turn on the key switch, and press the reset button. Make sure the “Water Protect” signal appears ON on the LCD screen.
Then, disconnect the water pump and check to see if the signal changes to OFF. If the signal turns off, that means the water protection function is working.

Note: If the LCD screen turns off, the automatic shutoff is working.

Step 6: Install Laser Software

The K40+ is compatible with popular laser software like LaserGRBL and LightBurn.

To install:

Plug the USB device into your computer and copy the contents onto your computer’s hard drive.
Install LaserGRBL and open it on your computer.
Install the CH341 driver compatible with your control computer system.
Connect the computer to the machine using the provided USB cable. Click “Connect.” If “OMTech” appears in the left console, it means the software has successfully connected to the machine.
Set the machine parameters and confirm them in the software to operate the machine.

After this, you can choose to install LightBurn to operate your machine.

Step 7: Mirror Alignment

Now it’s time to make sure that your mirrors are aligned:

Turn the machine on. Rotate the potentiometer counterclockwise to set the power to around 15%. Attach a piece of tape to the front of the third mirror.
Move the laser head to the upper left corner and close the lid.
Press the reset button to turn on the LCD screen, and press the red test button. Then, move the laser head to each of the other three corners and press the test button at each corner.

The laser will scorch the tape at all four corners. If the optical path is aligned, the spot at all four corners should overlap.

Step 8: Focus the Laser

A properly focused laser beam is critical for clean cuts and crisp engravings.

Place a piece of test material (like wood or acrylic) on the bed.
Manually adjust the laser head height using the focus tool or jig provided.

Once focused, you’re ready to run your first test.

Step 9: Run a Test Engraving

Open LightBurn or your chosen software and:

Import a simple design: a text, logo, or shape.
Set your speed, power, and layer settings (e.g., 15% power, 300mm/s for engraving wood).
Use the frame function to outline the work area before firing.
If everything looks good, hit “Start.”

Watch closely as the laser engraves your design. Keep your hand near the power switch in case of emergency.

Final Tips Before You Create

Never operate the laser unattended.
Clean the mirrors and lens regularly to maintain accuracy.
Only use laser-safe materials—never engrave PVC, vinyl, or unknown plastics.
Keep your workspace ventilated and fire-safe.

Wrap-Up: Your First Step Into Laser Crafting

That’s it! Your OMTech K40+ is now fully assembled, connected, and ready to bring your creative ideas to life. From engraved signage to intricate gifts and custom labels, this compact CO₂ laser packs big potential into a small footprint.

Ready to Create with Confidence?

From desktop engravers like the Polar+ to industrial-grade workhorses like the Pro Series, OMTech offers a wide range of solutions tailored to your needs and experience level. Each machine is backed by U.S.-based customer support, a growing online community, and educational resources to help you grow confidently.

Explore OMTech’s laser engravers today and discover how the right machine can transform your ideas into precision-crafted reality. OMTech is here to fuel your creativity, one laser cut at a time.