• Table of contents
• K40-III
  • Control board - 6c6879
    • Connectors
      • Y stepper cable
      • Flatcable for X stepper and endstops
      • Power and Laser
  • PSU
  • Hooking it up
  • Other Notes

K40-III¶

This is a cheap Chinese built laser that comes with a couple of different control boards, and some proprietary software.

Control board - 6c6879¶

This board uses a flat ribbon cable for X axis motor and both X and Y limit sensors, a 4 pin JST connector for the Y axis motor, and a 6 pin connector for power and laser control.

Connectors¶

Y stepper cable¶

Color	Signal	Connect to
RED	XA+	J18.2 A
BLUE	XA-	J18.3 A
YELLOW	XB+	J18.4 B
WHITE	XB-	J18.5 B

Flatcable for X stepper and endstops¶

Pin	Signal	Connect to
PIN12	XA-	J24.1 A
PIN11	XA+	J24.2 A
PIN10	XB-	J34.3 B
PIN9	XB+	J34.4 B
PIN6	COMMON	J34.4 GND
PIN5	XHOME	J34.2 XHOME
PIN4	YHOME	J34.3 YHOME
PIN3	+5V	J34.1 Vsensor

Power and Laser¶

Pin	Signal	Connect to
1	Not Connected
2	Laser
3	5V
4	Not Connected
5	24V
6	GND

PSU¶

The PSU has 4 connectors.

1. K+/K- - Laser Test button
2. G/IN/5V - Power control potentiometer
3. D+/D- - Laser enable/safety interlock
4. 24V/G/5V/L - Power to controller board

Our K40-III had a completely different power system. Also the Moshidraw boardand cabling we replaced didn't use the 5V rail that PSU generated, but you can (if you don't want to add the wire) use the 7805 to drop the 24V line to 5V.

Here are some photos of this PSU

Hooking it up¶

K40-III 6c6879 Connections to Laos board
K40-III Material Settings
K40-III Improvements

Other Notes¶

This machine is not what you'd call up to standards. Please bear in mind that there is no:

• Lid sensor
• Sensor to see if water is flowing
• Laser temperature sensor
• Cutting area temperature sensor to monitor for fire
• Extractor sensor to make sure fumes are being extracted.

Buy and operate this machine at your own risk. It is cheap, but you get what you pay for. In the K40-III Improvements will be some circuits to overcome some of these issues.