Hey all,
I’m trying to figure out why i can’t cut through 1/2" or even 3/4" wood thickness with my 150w laser. I saw a video on YouTube where this guy is talking about S-value max setting should match (laser output vs potential power). This seems to be for GRBL lasers/GRBL intensity. I am not sure what settings I need to adjust so I am looking for help so i don’t end up with ‘scorched earth’ edges. Suggestions most welcome.
Upload the *lbrn2 file with the offending non-cuts so we can take a look at the settings.
Useful information:
Do not assume a new-new machine will arrive with correctly aligned mirrors.
Which, as you suspect, doesn’t apply to Ruida controllers, because they have a binary command language, not readable G-Code. As a result, they do not use the LightBurn Console, do not have macros, and generally lack much of the tweakability found in GRBL controllers.
Reading through this may give some background:
If it’s a new machine, the controller is likely configured properly. Except, alas, for the X and Y axis PWM Rising Edge Valid settings that should both be False.
so this is not a new laser machine; i will inspect and clean the mirrors/lenses to see if that is the problem or part of the problem. I will admit, the mirror alignment seems to be fine.
The reference to PWM Rising Edge Valid settings - i’ll admit, this is completely foreign speak to me. Thank you for the reference “configuring ruida controller” i will dig into . I am attaching a file /project that I was working on tonight. My laser machine performed POORLY - i was cutting on 1/4" maple and had to run 3-5 passes (which is well beyond what I experienced in the past). I don’t know if the cold weather, cold water in the chiller has any affect??? I am working with Lightburn V 1.7.04.
sparta.lbrn2 (55.2 KB)
Considerable experience around here suggests that we cannot assume anything is correct inside that machine, so let’s start from the basics.
Your title says “CNC dual head lasers 150w + 60w”. Is it a custom-built CNC conversion or a commercial unit?
If it’s a custom rig, photos will help; we loves us some good custom hardware builds around here. 
If the latter, what’s the manufacturer name & model number. Something like OMTech USB-6R57, which is typically on the data plate somewhere.
How big is the platform? Knowing that helps set expectations for how closely the mirrors must be aligned.
Knowing the specific controller helps understand the configuration. Something like Ruida RDC6445G, which is (usually) printed on the controller box inside the electronics bay.
Does the 60 W laser head work / cut correctly?
The C00 cut layer in the file is set for 10 mm/s, which may be less than the machine’s Start Speed configuration. If that’s true, the controller will throttle the laser power to the 20% Min level, which is probably too low to do anything.
As a first test, set the layer’s Min power to 60% and run the job again. If that gets better results, then some other problems become less urgent.
As long as the water is liquid, it’ll work, but keeping it around 20 °C seems to improve the laser’s performance. Some folks use immersion heaters to get the “coolant” up to spec in the morning and prevent it from freezing overnight; ice is the tube killer.
Ed, with you in that I don’t assume anything was set up correctly. LOL
This is not a custom-built CNC laser machine; it is a commercial unit. Wish I was that kind of cool, but sadly I am NOT! So, I am working with CNCWL-6340 unit with a a workable 63" x 40" bed size. This operates via Ruida RDC6442S-B(EC) controller. Both laser heads work; i use the 60w primarily for engraving and the 150 for cutting.
I will say that the chiller is registering at only 14 *C (we have been under freezing temps for the past couple of days here in TX) so I had some concern as the chiller did not reach 23 *C
In as far as the lenses (stock C02 lenses), I will give them a cleaning today to make sure they are free of smudging or hazing. I have seen conflicting videos on lens positioning inside the housing piece. Should convex side face up or down? Some same the FLAT size should face down (convex size faces UP) - is this correct?
If you assume at least half of what you see on the InterTubes is wrong, you’ll be mostly right.
The convex side of the focus lens should be upward, with the flat (or in some cases concave) side downward.
With the beam traveling more than ten feet to the far corner, careful mirror alignment is vital. As much as possible, keeping the beam in the middle of the mirrors will prevent other weirdness out where the spot meets the material. Given the machine’s history, that may require moving the mirror mounts, but you can worry about that when it comes up.
From what little I can find on the Interwebs, a CNCWL-6340 is an orphan. Nothing wrong with that, as it seems many machines with a pedigree don’t get much more customer support.
My Basement Shop now trips the chiller’s 14°C lower limit, so I must start the “chiller” an hour before doing anything so it can warm the water: its pump is water-cooled. Perhaps if you let yours idle for a while, the temperature will climb a bit, but AFAICT anything within ±5 °C of 20 °C should be fine.
When you get the lenses & mirrors shined up, set the controller for a short pulse (Z/U → Laser Set → Manual, then set the duration in milliseconds) at a low power (Laser button, then set %) to scorch some tape at the mirror. Upload pix of the results at the entry to all three mirrors for the gantry / head both near & far. Use a fresh target for each pulse to eliminate the ambiguity of “Which one did that?”.
Then we can look over your shoulder and see what’s going on.