22. PLH3D-2W ENGRAVING LASER HEAD
This sub-assembly is a medium 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 the lens from dirt and cooling the laser head.
PLHD 3D 2W driver ensures proper work of the laser head and protects laser diode from overheating. During normal work green diode is turned on. When the laser head reaches 40 degrees Celsius second LED diode starts to glow. At 45 degrees the laser head switches off.
Turning the collimating lens allows changing the beam focus distance. Airflow from the fan keeps the lens clean during operation.
You can use two types of the 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 is making bigger optical power loss allows obtaining a smaller beam spot 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 the PWM signal which is fully compatible with PLH3D driver. High-speed modulation (up to 100 kHz) allows using of high movement speed during engraving even complicated patterns.
The module is using brand new NDB7875 450 nm diode which is one of the strongest available on market blue laser diode. Recommended power supply unit is 12 V with current capacity at least 2 A. On our website, there are available DC-DC converters which allows to easily change any higher voltage into 12 V.
The lifetime of the laser diode given by the manufacturer is 10000 h.
It is also possible to buy a version with an additional aluminum holder which allows mounting the engraving laser head on the moving part of the machine.
Main advantages of the PLH3D 2W:
- Easy connection to all 3D printers and CNC machines producers.
- Dedicated software - G-code generator
- No need for additional cooling.
- Simple installation to all 3D printers and CNC routers
- A driver attached to the laser head.
|Dimensions of laser head (LxWxH mm)||30 x 30 x 68.5|
|Modulation voltage range (V)||0 - 5|
|Modulation type||TTL or analog|
|Input voltage (V)||12|
|Mounting holes distance (mm)||20|
|Focus distance (mm)||20 - 120|
|Diode power (W)||2.8|
|Maximum power consumption (W)||15|
|Example beam spot size at 80mm distance||0.1 x 0.18 mm|
|Internal part no||001633|
Connection of the laser head
Connecting the engraving laser head is very simple and is using the 4-pin connector. To each device, the 4-pin connector is included.
Remember to use both GND cables
Pins #3 and #4 should be connected to the proper power supply unit which also can be bought at our website or together with the laser head. Pin #2 should be connected with GND of the modulation signal source while pinning #1 to the source of 0 - 5 V signal which is responsible for power modulation.
1 – Analog in 0-5 V
2 – Analog GND
3 – GND
4 – Vcc 12 V (minimal current provided: 2.5 A)
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 best for you.
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 the CNC machine. Focus depends on the type of lens used and their distance from the laser diode. Remember, do not change the position of the lens while the laser is operating. Switch the laser every 0.5 turns of the lens in order to check the 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 the range between 120 and 40 mm. For a single element lens, it should be in the range between 100 and 20 mm. Nevertheless, accurate focus distance should be set according to the test made with your material.
- 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 - 480 nm 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 input can be used as TTL/PWM input with its logic levels of 0 V and 5 V or as an analog input. 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.
Airflow is very important during the engraving process since it is blowing out dark smoke which can cause an optical obstacle for a laser beam.
This module has a thermal protection system which protects laser diode from overheating.
The analog input is protected by a 5V1 Zener diode on occasion there appears the voltage higher than 5 V. Despite everything, this input should not be used with higher voltages.
The output of the driver is protected by Schottky diode which doesn't allow the reverse voltage to appear.
Dimensions of the PLH3D – 2W
Dimensions of the aluminum mount
PLH3D 2W with aluminum holder
Additional components (depending on the set, different parts are included )
PLH3D-2W with ABS nozzle
Parameters of cutting
Note, that these speeds and parameters are effects of tests and can be different for some materials, cooling systems as well setting of the focus distance.
Binder board 3 mm: 5 mm/s; 2 W; 8 x 0.5 passes
Balsa 5 mm: 25 mm/s; 2 W; 5 passes
5-layer cardboard 5 mm: 10 mm/s; 2 W; 4 x 1.25
Rubber 0.5 mm: 15 mm/s; 2 W; 3 x 0.25
Jeans 0.5 mm: 8 mm/s; 2 W; 1pass
T-shirt 0.5mm: 25mm/s 2 W; 1 pass.
Glass fiber reinforced foil (dark) 0.3 mm: 3 mm/s, 1 pass.
The laser has no effects on: