yes it is wright i just post my test result and for the5 volts TTL I used PC9 and ground sideways i used M3 S255 to get 2.5 volts
and for the 12 volt TTL signal i used the M106 S255 to have 12 volt on the PC8 FAN0
i will do the test whit this file and let you now what outputt it used and what voltage !
Just to make sure you understand, the strength of a laser does not depend on the voltage (assuming you are using a voltage the laser module accepts). The signal is turning the laser on and off rapidly. If the on/off is split evenly (S128), then the laser will be at half power. In terms of driving a 5V laser module with a 3.3V pin like is on the SKR Pro, as long as the 5V module laser accepts 3.3V as “High” and therefore will turn on, it will work. The reverse is not true. You don’t want to drive a 3.3V device with a 5V signal.
The fact that you get 2.5V using M3 S255 is a bit strange to me. You should get around 3.3V from the SKR Pro.
finally i found the problem for both M3 and M106 command !
i had modify the firmware to activate the M3 command to activate an external relay to activate my dewalt router , my relais was cliking and drop the voltage , so i unplug the wire for this relay and everithing whent back to normal PC9 is working fine whit 3.3 volts it will be good for my heavy 40w laser because it used the TTL whit 5v max !
so i will install a switch to my line of the relay for the dewalt router to desactivate it want to used the laser !
and i will create a grill patern to test both laser power for each laser !
thanks for all your time it help me to find my problem !
OK last update on the laser setup !
i install a 40w laser and using the PC9 and the ground just next to it the voltage is 3.3volts max , is there a way to configure the PC9 to have 5 volts because i can not get the full power of the laser ?
This post pushed my Laser Build (and upgrade to SKR from Archim over the finish line. I have some small changes from what’s above due to changes in Marlin. I’ll write it up once I get a few things polished.
Here’s my cut result:
Here’s the Gcode for any who need a test:
https://drive.google.com/file/d/18zCDspIo_OiIdfaljyrgctzSoKAkO1VQ/view?usp=sharing
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OK last update on the laser setup !
i install a 40w laser and using the PC9 and the ground just next to it the voltage is 3.3volts max , is there a way to configure the PC9 to have 5 volts because i can not get the full power of the laser ?
What indication do you have that you are not getting full power? Most of the lasers you buy off the internet will be way overhyped or even scams with respect to their power. They quote input power to the laser, not optical power, or they just plain lie. As for the strength of the laser, it does not depend on the voltage of your signal. The signal is just rapidly fluctuating between full high and off. The amount of time is spends high vs. off determines the strength percentage of your laser. Typically a device that expects a 5V PWM signal as input will work with 3.3V signal since the 5V device will interpret anything over 2.5V as an “on” signal.
If you have a 5V power supply, you could, removed the connections to the SKR pro board, and try feeding your laser signal pin and the ground connection from that 5V source and compare the laser strength to what you get with your SKR Pro when you set PWM to 255. If there is a big difference, then the next thing I would look at is if the PWM input values are somehow different for the SKR firmware than the Rambo firmware. A 32-bit board has the ability to have an expanded range of PWM values, but I doubt the firmware maintained by V1 or even Marlin in general is setup this way.
If you really need to convert the voltage, then you can use a logic level converter like is described in this writeup. You have an added problem in using this kind of board in your setup because you have to provide 5V source voltage to the 5V side, and currently neither the laser nor the SKR board has one.
i look to the screen and it say 255 on the laser icon because i am using the M3 command i am using the laser Amazon.ca
i already post them the question becauce it is supposed to be a 40w laser and waiting for them to answer i dont now if it is deffective it is working good for engraving but it does not cut MDF 3MM at full power 255 at 10MM/S i will try unplug the TTL and putt the switch to on to see if it make difference , i just make the test and nothing change the laser must be defect or is not really a 40W laser !
This is definitely NOT a 40 watt output laser. There are two common power ratings for these lasers, 1) input power and 2) optical power. Typically optical power is 1/3 to 1/5 of the input power. Without proof, I suspect this is a 10 watt optical power laser at best. I’m no expert, and I’ve not seen any reviews, but the best diode lasers in the open market that I’m aware of achieve 13 watts to 15 watts of optical power, and use two laser diodes focused using a mirror to accomplish the task. Here is one example. Not all MDF is the same, but for this NEJE example laser, 3mm MDF would probably be two passes at 4mm/s, or maybe one pass at 2.5mm per second, both with air assist.
Note in the link you provided, they indicate the laser has 25 watts of “Focus power” whatever that is. I would love to see/own a diode laser with 25 watts of optical power at this price point, but I don’t believe this is one.
i suspect me to it is not a 40w laser i think i will buy an other laser i am thinking off this one
what is air assist means exactly ?
if i putt Laser air assist for dual fans by Spacegrey - Thingiverse
whit twoo fan is it ok ?
The one at the new link you provided is 6W optical. I’ll bet it is weaker than the one you already have…probably substantially weaker. I would not buy from Amazon. Buy directly from the manufacturer if you can, and buy a laser that is popular where you can watch YouTube videos and compare your cutting numbers to the ones in the videos. The scams and hype around these diode lasers is appalling, and it is very difficult to figure out what you are getting.
thanks
With laser cutters/engravers, air assist is blowing a constant stream of clean air into the cut. This clears smoke and other waste products of the cutting process out of the beam. This improves cutting efficiency (cut deeper at same power settings) and helps to prevent flameups during the cut. Some industrial laser processes benefit from using specific assist gasses, but for the home/makerspace/small business environment, a small airbrush compressor or large aquarium pump is often used to supply regular room air.
This is in addition to any exhaust system used to remove the smoke or other fumes that result from the lasing process from the work area.
cool i just fit a duck whit fans to blow air i hope it will do the job !
thanks for the information
i will do the same file after whit diferent setup in lightburn !
i think the laser is no good i send an email to the seller i tryed 2.5mms full power 2 pass whit lightburn setup and it cut only .4mm it is definitivelly a defect laser or a crap one !
In my (admittedly limited) experience, to be effective, the air assist needs to be targeted on the laser’s focal point on the material. The goal is to blow clean air into the beam area to prevent scattering of the beam by smoke, etc. and to “blow out” flame ups before they get started. I’m using a small aquarium air pump on my K40, but the pump is located outside of the enclosure so the air is clear, and it runs through vinyl tubing to the laser head. I’ve used a variety of nozzles, from 3D printed attachments to .035" welding tips to get a focused jet of air that can be directed to the cutting point. I can definitely tell the difference when air assist is aimed right, and when it isn’t doing the job.
From the photos, I’d expect those fans are just circulating already smoky air back into the cutting area. I would expect that would waste more power lasing the smoke and scattering the beam, rather than improving your cuts.
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i try to order from NEJE site and it does not work i already order the laser NEJE A40640 i think this one will be better for my job i like to do !
what model did you used for it ?
i would like to buy it but i dont now whitch model order ?
is this one could be good the 100w model ?
I see a lot of people online are using those. I spent $12 at my local pet store for a much smaller pump. It was several years ago, but I think it was sized for 15-20 gallon tanks. Not the smallest they had, but it didn’t make sense to me to spend big bucks on an air pump.
thanks for the information it will guide me to whitch one i will buy !