I am not new to CNC, but I am setting up my first laser engraver. I have a couple of laser modules - one listed at 5.5W from a failed start a while back, and one listed at 40W. I have no dilusions about the Chinese not lying to me about power, but they were cheap enough that they should be worth the money.
Speaking of the quality of cheap diode laser modules, I know not to run them at full power and that they have two failure modes - the diode and the driver. I fully expect mine to go bad and that is where the DIY portion comes in. For the diode, I have ordered a couple of NUBM08 (because they are 1/3 the price of NUBM44). But I am going to need to drive them and I don’t picture the cheap driver to last long.
I could drive the diodes with a CC/CV unit and keep it from blowing up, but I wouldn’t be able to use the PWM output from the GRBL, so it would be fairly useless. I could buy one of the diode controllers from one of the laser sites, but I don’t see where any of them accept GRBL control and their controllers cost as much as a whole laser unit, anyway. I could do something “hackey” and feed a diode with a CC/CV supply, then control it by interrupting the negative lead to the diode with a MOSFET controlled by the PWM lead from the GRBL controller. But that seems too easy.
As cheap as GRBL controllers are, and as cheap as these diode units are, has anyone produced a drop-in diode driver? Is there a better DIY option?
Thanks for the reply. Using the word “lie” may sound harsh to some, but it wasn’t a flippant comment. I did find a Chinese company who is selling controller boards and was able to be honest with me about their power numbers. Their 40W board is able to handle 2A at 12V and their 80W board is able to handle 4A at 12V. Some 3rd grade math will show that those numbers don’t add up. I have trouble coming up with a gentle way to state “misrepresenting basic math.”
I do, however, appreciate this company communicating with me and giving me honest information I can work with, so I will be buying products from them. And, if I need to modify their products to make them work for me, I already know that going in.
I have seen a laser/CNC controller board running GRBL where I ordered my AtomStack for less than 40€. Not sure that’s what you need but just in case the keywords would be “New 3018 CNC Router 3 Axis Control Board GRBL USB Stepper Motor Driver DIY Laser Engraver Milling Engraving Machine Controller” ( yeah, they really go nuts on their product name but it looks like it pays )
Thanks for the controller link. I’ll be buying one of those boards, but that’s not what I need right now. As it happens, I will have two of these machines. I will use one for routing aluminum and the other for laser. When I first started looking, the 3018pro seemed to be the best thing available. But it’s more than obvious that the spindle it comes with is but a toy. You really have to use the 500W spindle if you want to cut aluminum. But you need an adapter to put the 500W spindle in the z axis. A little searching will pull up a z axis on Aliexpress that is designed to put this spindle on the 3018pro for less money than what my time is worth. A couple of failed attempts at purchasing one of those makes you stumble across a 3018plus - the 3018pro with all metal construction, stepper motors, and it accepts the 500W spindle (but no controller). So I did the only logical thing and ordered the machine I should have in the first place to put my electronics in. I’ll probably finish the router and the laser about the same time. I won’t be at a loss because I will have two separate machines designed to do two separate things at the same time.
I can post an update on how it went, but It won’t be finished in a couple of days. I have to wait on multiple pieces to come from China and I’m sure everyone knows that can take a bit.
)