Does LaserGRBL contains virus or malware?

LaserGRBL is open source, it mean that everyone can see its source code and check if the program can do something malicious: it does not do.

However it was reported that some antivirus warn about potential malware:  these reports are false positives usually caused by heuristic engine. Read more

LaserGRBL can also trigger some firewall. It’s all normal: LaserGRBL connect to internet to check for its own updates


LaserGRBL is compatible with Windows from XP to W10.
64 bit OS is strongly suggested in order to use all the features of LaserGRBL.

LaserGRBL need Microsoft .NET framework installed on the machine. This is by default in W10 but for older Windows version you shoud download and install from internet.

There are no special hardware requirements, but more RAM and better CPU provide better speed performance in the image processing.

On Intel i7-7700 with 16GB an engraving of 400x600mm @ 10 lines/mm (24 megapixel) is processed with dithering engraving in about 2 min. producing about 14’000’000 lines of gcode.

MAC or Linux version?

Sorry, LaserGRBL is only for Windows.

Does LaserGRBL work with my engraver?

LaserGRBL work with any engraver that use Grbl as controller. This also include a lot of mounting kit from ebay, bangood, aliexpress, amazon, based on arduino uno/nano or other customized boards with ATmega328P chip.

Often some of these markers do not use Grbl but they use other control firmware/protocols (benbox or others) but is it possible to reprogram their firmware to use Grbl. You must google about how to do that with your specific controller.

What engraver to buy?

LaserGRBL can work with any type of grbl-based engrver but we suggest ORTUR product because they have a very good LaserGRBL compatibility and they are quality-price saving.

ORTUR Laser Master II – 400mm x 430mm – 7W/15W/20W options

Read “BUY” section for more info.

LaserGRBL does not connect to my engraver. Why?

As already mentioned LaserGRBL work only with boards that implement Grbl. If you are sure that your board is Grbl compatible and you experience connection problem please verify that you are using the proper COM port and connection speed.

I need buttons for trace border, center etc

LaserGRBL allow to add as many buttons as you want with a feature called “custom buttons”.

Add custom button

Help! Some buttons/options is missing

LaserGRBL detect GRBL configuration and remove (hide) some options if not compatible with your firmware/configuration.

  • M4 Dynamic Laser Power Mode is available only if your controller is updated with Grbl v1.1 or next, with “laser mode” enabled in grbl config ($32=1)
  • Homing button ($H) is available only if Homing feature is enabled in grbl config ($21=1)
  • Speed and power override is available only with Grbl v1.1 or next
  • Line2Line engraving needs PWM support, if you uncheck “Support PWM” LaserGRBL remove the options
  • Centerline tracing is available only on 64bit OS

This list includes the most common cases, but it is certainly not exhaustive.

Wrong job size, axis direction, to fast or to slow movement

Hardware need its own configuration that is stored inside controller board. This configuration is accesible via menu “Grbl – Grbl Configuration”

I have written a guide to most important parameter. Please read this page and download the guide.

Weird result, hang, reset or errors.

Grbl was widely used and claim to be stable and and robust. Also LaserGRBL was strongly tested and does not show evident issues. Both can manage programs with million of gcode lines without problem.

However some user experience issues of valid gcode lines reported as error or random hang/reset during engraving. Why?

It is difficult to answer these questions in a general way. Every engraver is different, different in power transformer, different motors, different cables, different drivers, different arduino clones (really few people use the original arduino, which has more reliable components and serial chip).

Common causes are

1. Underrated Power supply

Current demand of motors and laser diode can be very high.
If the power supply is underrated it is possible that its output voltage drops, causing the control board to reset. Make sure the power supply is strong enough for your engraver.

2. badly plugged cables, damaged USB connectors

USB sockets and connectors suffer from deterioration with use. Check the good connection between the connector and the plug, if necessary try a different USB port or a different cable.

2. Electrical noise generated by stepper motor

Stepper could generate very strong electrical spike on power line that can go back to USB line. The cable is the first inquired. In my experience I have tested 3-4 different cable and only one is 100% reliable. The good one is a samsung phone data cable. Good ones should be short, thick (well shielded) and possibly with ferrite.

If you use a laptop plug it to the power line and do not run with battery. Doing this you have grounding through main power line.

Place your USB cable far from motors and DC line, to minimize induced noise.

Add a pair of capacitor parallel to DC line, one elettrolitic of 47uF 50v and one ceramic of 0.1uF. this is called “decoupling” and could help in case of electrical noise.

3. High stepping resolution with high feed rate

Grbl is awesome but Arduino is a limited hardware.
If you use a high step/mm and you want to perform very fast movement Grbl should generate a lot of stepper pulse. Generating pulse is not the only work for Grbl: it also manage communication, check for limit switch and hardware buttons, send position and status etc…

If you are asking your Arduino to do more than it can do you could experience issues. In this case you can try to:

4. Poor quality arduino clones

For original Arduino, quality matters the most. They do use best smd/through hole components, best pcb fab house they can get. The boards are fully tested before being shipped.

The clones/compatibile are cheaper, but to reduce cost they also reduce quality and reliability.

Even if the clones normally work well sometime some clone could be faulty. Sometime this faulty is evident (they simply doesn’t work) sometime they are more subtle. They look working but sporadically has issues specially when stressed.

If you experience random issues and everything else fail try using a different Arduino board.

Also note that clones with the CH340 serial chip suffer from communication problems, while the arduino (original or clone) that mount the 16u2 chip did not show any sort of communication problems. (read more)


LaserGRBL can slow down its TX/RX thread to prevent serial communication problems with poor/faulty Arduino clone; try with this set-up if everything else fail.