since I up graded from a 20 watt laser to a 40watt laser on my Xtool D1Pro, Lightburn is unable to locate X=0,Y=0. it would just sit there and rattle until it times out. If I switch back to a 20, it works fine. The 40 watt has larger footprint.
Is there away to change the Home key not to go to x=0, y=0? maybe x=1, y=1mm
Not using the home key. But you should relocate the limit switches to make the bigger module fit.
I helped a friend make that exact same conversion on his D1, and I do recall remounting the limit switches as part of that process. I’m frankly surprised that xTool is not using Trinamic drivers for their stepper motors. They have the ability to use back EMF to detecting homing–no physical switches needed at all. They have worked flawlessly on my two Prusa filament printers for five years now, and I have used them in a few ESP32 (Arduino) projects as well.
I understood it was the increased current load … Do you have some sort of information about these?
I always thought this was smart for a low cost machine.
Not really applicable to machines like the Ruida…
Back EMF is the term used for energy in the stepper motor coils that reflects back into the driver, and when it goes high enough due to a motor mechanical stall load, the Trinamic driver flags it on a “Diagnostic Pin” connected to the parent micro-controller. Trinamic Inc., a German company, invented it and calls it “StallGuard 2”. It has to be designed into the wiring and the firmware from the get-go, so it’s not a drop-in opportunity for an xTool. Trinamic is now owned by a company called Analog Devices. When I assembled my D1 I was surprised it did not use that technology. I haven’t checked what drivers they are using.
Thanks for the clarification… I wasn’t aware of the process.
The D1 homing I thought did use back EMF for sensorless homing. I don’t know if they were using Trinamic drivers for it. I assumed they moved to proximity sensors on the D1 Pro because of how poorly their sensorless homing solution worked.
Ortur has ironically gone in the other direction using sensorless with the OLM3.
From my experience with sensorless homing on 3D printers I’ve found them good enough for general applications but never as good as a dedicated solution.
Car makers have been using the same concept on car power windows for years. There are no limit switches on the window.
Today’s lasers travel 200+ inches per second, or other units of measure. Having a gantry run up and slam into a frame until it stalls is not my ides of good engineering.
I wasn’t aware of this. I know on at least one of my cars that if I ever disconnect the battery I need to go through a learning process where I completely open the window manually, then close. I wonder if this is to recalibrate to actual current levels at stall as it changes with motor age…
I’ve never seen a gantry machine run at >16 feet a second … overscan must be tremendous.
Could you post a link… ?
There is a home speed in controllers so they don’t run at full speed during boot and slam into things. Most of the larger machines I’ve seen have home and limit switches… I like the concept of the motor handling this, but it’s probably not very applicable to large machines.
Mine homes relatively slow, but really rips when it’s goes to the user origin after a home operation.
Don’t type with fingers that shake. That was supposed to be 20+ ips (6000mm/m is 19.69 in/s).
I have direct experience with three Prusa printers that I use nearly daily, two Mark 3S+ that I’ve owned for over 4 years now, and one Mini+ that I bought last year. All axes have Trinamic drivers, and for every print job they home the X and Y axes using the StallGuard technique at a relatively slow speed, and that has been flawless. The z axis has a contactless probe that does a 9 or 16 point “bed leveling” measurement. After that, they keep track of where they are by calculations in the firmware, and I have never experienced any collisions of any sort.
I have direct experience with three xTool laser engravers: an early 10 Watt that I converted to a 20 Watt, a second one that I bought as a 20 Watt, and a third bought as a 20 Watt that I converted to a 40 Watt. Every homing command for them has been executed perfectly (slow speeds and no chatter). But operational runs do not automatically include a homing run, and during my learning curve with “origins” I certainly drove them into hard stops at operational speeds with the resulting chatter. No damage so far, and I’m getting better.
And I can understand why 3d printers always do a homing run: they start with an empty bed, whereas laser engravers have a target “canvas” to hit. Like I said, it was a learning curve…
I used to be a CNC Technician. I view this stuff from a different perspective.
Diode laser output power?
I can imagine that serious CNC machines could be damaged by driving into hard stops, but these 3d printers and laser engravers use relatively tiny NEMA 17 motors, which seem to survive without damage. Don’t get me wrong; I make every effort to avoid doing it, but with engravers it happens. It never happens with my 3d printers because they always home before every operational run, they know the physical limits of each axis, and they keep track of where they are in the firmware. I’ve never had a collision.
As for power, yes, I was talking about the maximum laser powers at 100% duty cycle. I find it curious that the tradition with laser devices is to quote power only in percent, without direct reference to the size of the laser. For instance, you won’t find any reference in the LightBurn Material Library about the laser power at 100%. I think that should be tracked in the metadata of the library as a minimum. Since I have lasers with varying maximum powers, I put the laser power in the filename of the material library.
Can you elaborate on your perspective?
I’ve got one 3d printer… it only homes on power up. I can’t see any advantage of multiple home operations… is there something I’m missing?
I think the Gweike homes before each job.
Do you have an instrument to determine your lasers output? Most of us don’t, so it’s kind of a nebulous area.
Using percentage values simplifies how the software → controller work. For your approach, you’d have to know the actual tube output, as would both the software and the controller. The software only controls the pwm, which is a percentage of duty cycle.
Some commercial machines use percentage speed… very elusive.
Sure! If somebody broke it, I was the one that had to fix it. My worst enemy was engineers that thought they knew how to Gcode program.
there is none with those machines. They use lead screws and you cannot manual push them out of sync with the controller. But you already knew that.
.
My Ruida only homes on power up or when you press the reset button… it has belts, if screws are relevant. All of my grbl machines home only on boot and when commanded by the user. Two are belt and two are screws…
What is the advantage of performing a home operation more than once? Any machine that tracks it’s location would not need that more than one home operation.
Still missing your perspective being different… unless it’s engineering …
Not being argumentative, I’d just like to understand what you mean.
I think the principal reason for 3d printers to go through a homing cycle for each run is bed leveling, not a worry about the X and Y axes getting out of sync, once they know where those axes are. Older machines did not have the electronics to save the positions of their axes if they were turned off, so they had to home at least once upon power-up to establish that. Also, they generally had manual adjustments for coarse bed leveling. If they had “automatic bed leveling” at all, they used a sensor to map deviations from a perfectly leveled bed, and those deviations were used by the firmware during any given run. Again, that deviation map was lost at turn-off.
Prusa printers do not have any manual bed adjustments at all–they just map the deviations before each run and correct in the firmware during the run. They have removable flexible beds to assist in releasing completed prints, and those beds may have a slightly different position when reinstalled for the next print. Additionally, the deviations are sensitive to the bed temperature distribution, and that varies if filament types are changed. And finally, homing and automatic bed leveling takes at most a minute, and if you’re doing a 3 hour print, it’s fully worth doing.