I recently bought a neje E80 laser module, quad diode, approx 20W optical output. I can report that its almost exactly twice as powerful as the A4060 dual diode, which is very nice. I like it. It comes with built-in air nozzle, quick connect airline port, and a second hooded nozzle were the hood can be adjusted down to the cutting surface to minimize reflected laser light. It used the same mount as the A40640, so it was easy to install.
Thus far my only (but minor) disappointment is kerf width; they advertise 0.06mm square fine focus dot. I suspect this small kerf is only realized when etching on hard surfaces and at very low power, < 15%, which I’ve not yet done. Cutting 3mm baltic birch ply yields a kerf of 0.24mm; 380mm/m, 85%pwr, 1pass, Zoffset 1mm inward. The kerf does seem to be fairly symmetrical XY, however the grain of the wood can cause it to measure asymmetrical at times.
Nominal focal length is 25mm from the base of the unit, mine tested best at a distance of 23mm, I assume some variance is to be expected.
All in all, I’m very pleased with it. It seems to be built well for heat dissipation with 2 fans and very beefy heat sink, visually more than twice the size and weight of the A40640. If I ever needed to run it at 100%pwr for brief periods I’m not concerned about that at all.
I selected the E80 because of my satisfied results using the smaller wattage neje A40640 module, and because I had a significant one-off discount available. I also was not aware of the K30 Laser Tree unit you reference. The specs and cutting parameters of the K30 are impressive for the price.
So the good news about the E80 unit is that it has plenty of power, so much so that I immediately began cutting 3mm baltic birch ply and 5mm luan ply in 1 pass. The speed (380mm/m) is nice but the pitch and tar residue that condenses on the CNC bed is awful. I use a 12x18" bbq grill as my elevated bed with aluminum sheet metal under it when doing cut through jobs with the laser. Fortunately the pitch and tar cleanup rather easily with Dawn and warm water, but there can also be staining on the wood which doesn’t clean up easily.
I didn’t have this much of a problem with less powerful lasers where I was using 2 or more passes to cut through. So perhaps that stands to reason since during the final pass there isn’t much material left to vaporize, that’s the theory anyway. So I experimented with 3mm BB by cutting through at 1000mm/m, 90% pwr, 3 passes. Dang! That seems to have minimized the pitch and tar condensate dramatically, to just a shadow, and the total cut time is only 13% longer. So the moral of the story here is- crank up the power and speed, run fast with multi pass
Finally, worth noting, the much larger heatsink and dual fans on the E80 keep it much cooler at 90 - 100% power than the A40640 did. Neje units have a built in temperature monitor so its easy to check and monitor. I have much less concern running the E80 in this range than I did the previous diode lasers.
Perhaps we’re not talking about the same E80 laser module. Here’s the laser module unit I purchased. Notice the DRO board included which drives the laser unit. Power and PWM w GND attach to this board. An optional second board, without DRO and push buttons is included also, not used in my case.
It may be as simple as a thermistor with variable resistance based on temperature. If you prove it out it would likely not be that hard to calibrate the relationship from resistance to temperature.
Maybe, I wouldn’t call this a major Chinese secret to tell us it’s output type with enough information so we could actually use it…
My machine isn’t in the house and I never bothered to check it with the scope, although I thought about it. I guess I was using it.
Next time I break it out, I’ll watch it and see what comes out…
It’d be tough with only a voltage that relates to what? I can’t find anything on even an upper temperature to try and calibrate it with… Have to know what temperature which is unknown as far as I can tell.
