LUNYEE CNC Controller Board GRBL, New GRBL 4Axis Stepper Motor Controller Control Board, with Offline/300/500W Spindle USB Driver Board, for CNC Laser Engraver

This is the 3rd time that I have purchased this 4-axis Control Board.The price is excellent and the components function nicely.Installing the board, including external stepper drivers, was simple.I have had no failures or negative issues. I purchased the first controller board 2 years ago and it's still a workhorse.The additional units are for ongoing projects/ CNC builds.I do recommend these boards very much.

I had high hopes when I received this board and installed it immediately. It lasted about 2 hours before the card stopped working. The symptoms were the motors stopped responding to the gbrl code. Not sure why but I assumed I may have received a semi defective card.

This CNC controller is working perfect. My only complaint is that it didn't come with a power source or at least the barrel connector itself

This control board works perfectly with my CNC router and laser setup. The compatibility with different motors and software is impressive.

I recently bought from Amazon two LUNYEE CNC Controller Board GRBL, New GRBL 4Axis Stepper Motor Controller Control Boards, with Offline/300/500W Spindle USB Driver Board, for CNC Laser Engraver.I installed them in two homemade machines for my personal use. One of the machines is a CNC router, and the other is a Laser Engraver. Both machines used to have Arduino GRBL shields, and they worked OK. The laser machine is driven with Lightburn software, and the router is with Gsender 1.4.10. The idea was to upgrade my machines with your 32-bit boards.Unfortunately, both boards show the same issue with the PWM outputs: the laser power or the spindle speed goes down to half or less of the maximum when running g01 or g02 /03 commands.The issue is the same in laser mode ($32=1) with M3 or M4 commands. The problem is always present with the M3 command in the spindle mode ($32=0)The problem is present when running a G-code program or with direct command of the console.The Laser machine settings are:$32=1$31=0$30=255The router machine settings are:$32=0$31=6000$30=12000An example of the problem is as follows:Machine: Router● Send M3 S12000 via the console● The spindle starts running at 12000 RPM● Send G01 X200 F100● X starts moving; the spindle speed reduces to almost half.● When X reaches the position, the spindle continues running slowly.● Sending a new S command does not affect the spindle speed.● Sending a M5 command will stop the spindle. A new M3 command will restart the spindle at 12000 RPM until a new G command is issued, and the spindle will slow down again.The laser machine behaves exactly as described above.After effort and time buying the boards, rewiring my machines to install the new boards, and being unable to use them, I am very disappointed with this situation.