16. PLH3D-6W LASER HEAD
This sub-assembly is a high power engraving laser head with thermal protection and professional high speed driver. Its design ensures that the head doesn’t require any additional cooling. Fan design makes it work as a fully customized air nozzle protecting lens from dirt and cooling the laser head. PLHD 3D 6W driver ensures proper work of the laser head and protects laser diode from overheating.
At 45 degrees the laser head switches off. Turning collimating lens allows to change the beam focus distance. Air flow from the fan keeps lens clean during operation. You can use two type of lens with our PLH3D laser heads. G2 lenses are popular because of the efficiency but it is not the most important parameter. While engraving, power density is more important - unfortunately G2 lenses are not providing small beam spot (while focused). Three element lens which are making bigger optical power loss allows to obtain smaller beamspot which helps to obtain bigger power density.
The choice is up to customer's requirements, since in some situation it is better to use G2 lens and sometimes three element lens. The laser head allows to cut or engrave materials such as rubber, wood, paper, leather, plastic, cardstock and many other. Thanks to full analog modulation it is possible to engrave in shades of grey or change the output power during turns. The same effect can be achieved by using PWM signal which is fully compatible with PLH3D driver. High speed modulation (up to 100 kHz) allows to use high movement speed during engraving even complicated patterns.
Module is using brand new NUBM44 450nm diode (capable of 6W) which is strongest available on market blue laser diode. Recommended power supply unit is 12V with current capacity at least 2,5A.
Lifetime of laser diode given by manufacturer is 10000h. It is also possible to buy a version with additional aluminium holder which allows to mount the engraving laser head on the moving part of the machine.
Main advantages of the PLH3D 6W:
- Highest available power in single diode
- Easy connection to all 3D printers and CNC machines producers.
- No need for additional cooling.
- Simple installation to all 3D printers and CNC routers
- Driver attached to the laser head.
Dimensions of laser head (LxWxH mm)
40 x 55 x 69
Modulation voltage range (V)
0 – 5 (0 – 24 for TTL input)
TTL or analog
Input voltage (V)
Mounting holes raster (mm)
24 x 15
Focus distance (mm)
20 - 120
Diode power (W)
Maximum power consumption (W)
Beam spot width (mm)
Beam spot height (mm)
0,2-0,4 dep.on focus
Example beam spot size at 80mm distance
0,1 x 0,4 mm
Internal part no
Connection of the laser head
Connecting PLH3D 6W laser head is very simple and is using 5-core cable. To each device 5 ways terminal strip is included.
Remember to use both of GND cables
white - Analog input 0-5V laser power is proportional to the voltage given on this input
grey – TTL in 0-24V all voltage given over 3V on this input gives maximum power and all voltage below 2,5V gives no power
yellow – Analog/TTL GND
green – GND
brown – Vcc 12V (minimal current provided: 2,5A)
Brown and green wires should be connected to proper power supply unit which also can be buy at our website or together with laser head.
Both ANG in and TTL in inputs can be used as PWM inputs. ANG in and TTL in should be used separately.
Additional single lens collimator is attached. Premounted three element lens collimator is 30% less efficient but it has 2 times smaller spot. You can check which one works the best for you.
PLH3D laser head has aluminium cover for a driver. It protects laser driver from dust and metal chips which may be produced during milling.
Setting the focal length/distance
Setting the focus distance should be firstly done by turning the lens and then, after making the lens not move, by using your Z axis in CNC machine. Focus depends on type of lens used and their distance from laser diode. Remember, do not change the position of the lens while laser is operating. Switch the laser each 0,5 turn of the lens in order to check beam spot position.
Be careful not to unscrew the lens accidentally – the lens can fall down and get dirty/destroyed. For three element lens focus length should be in range between 120 and 40mm. For single element lens it should be in range between 100 and 20mm. Nevertheless accurate focus distance should be set according to the test made with your material. Front cover should be put back in its place after setting the focus.
• Remember that it is not a toy. Laser radiation is dangerous even when scattered or reflected from any surface.
• Always use proper protection laser filter on your CNC machine dedicated to 430 - 480nm in order to avoid reflected radiation.
• Never point laser head at people or animals.
• Do not touch the beam, it may cause burns.
• Do not stare at the beam or the beam spot while the material is being cut.
Recommendations and requirements
Modulation TTL input can be used as TTL/PWM input with its logic levels of 0V and >3V (24V max). Analog input can be used as both: analog modulation or TTL/PWM (but 5V max). Analog modulation means that by using 2,5 V on ANG input you get 50% output power, analogically by using 4 V you obtain 80% output power, etc.
Cleaning the optics is important since dirty optics reflect some % of power back to the diode what may be damage it irreparably. Air flow is very important during the engraving process since it is blowing out dark smoke which can cause optical obstacle for a laser beam.
This module has thermal protection system which protect laser diode from overheating. Both analog and TTL inputs are protected by Zener diodes on occasion there appears voltages higher than acceptable. Despite everything, those inputs should not be used with higher voltages. The power supply input is protected against a reverse and too high input voltage by a transil diode. Transil diode will not protect laser head in every case, please be careful when connecting the power supply. The output of the driver is protected by Shottky diode which doesn't allow the reverse voltage to appear.
Dimensions of the aluminium mount
Dimensions of the fi43 nozzle
PLH3D 6W XF with fi43 nozzle
PLH3D 6W XF with aluminium holder
Additional components for PLH3D 6W
Parameters of cutting
Note, that this speeds and parameters are effects of tests and can be different for some materials, cooling systems as well setting of the focus distance.
Balsa 5mm: 30mm/s; 6W; 5 passes
Fiber-reinforced foil (green): 0,1mm: 50mm/s; 6W; 1 pass
Rubber 0,5mm: 15mm/s; 6W; 3 x 0,25 passes
Cardboard (0,5 mm): 8mm/s, 1 passes.
3-layer cardboard (1,4 mm): 20mm/s, 3 (0,5mm step) passes.
5-layer cardboard (5 mm): 10mm/s, 4 (1,25mm step) passes.
Polyfoam (15mm): 8mm/s, 2 (10 mm step) passes.
Polyfoam (24mm): 5mm/s, 2 (10 mm step) passes.
Leather (1,7mm): 5mm/s, 2 (1 mm) passes.
Jeans 0,5mm: 8mm/s; 6W; 1 pass
Green Plexiglass 3mm: 2mm/s 2W 6x0,75 passes.
Red Plexiglass 3mm: 2mm/s 4x 0,75 passes.