Now that this controller runs as it should, I was wondering how I can get the E0 stepper ro drive a second Y-axis motor. Can someone explain? Thanks!
Well, It was a newbie mistake, but since the previous message I found that E2 already is configured to act as second Y. I do not need a second X though, will that be problematic for homing? Do I need to disable X2 and compile again?
Also I am noticing my Z steppermotor (a Nema14 0,5A) to get VERY hot and making a high pitched noise with a gliding frequency. I tested the motor and it does turn both directions as instructed, but it gets very hot and I feel the need to switch off within a minute.
I’ve been playing with the $140-144 commands (stepper motor current), but they do not seem to make ANY difference. They are default at 135, but I am thinking they might need to be a value 1 to 100, or a “real” value giving the needed Amps (like 1.6 for regular motor, and 0.5 for this Nema14). The other motors have no problem with the max current the Rambo puts out, but this Nema14 probably does. But putting 0.5 in for the X motor does not make ANY difference to the holding torque compared to the value being 135, or 1.35 or whatever. So the Nema14 Z motor keeps making the noise an getting very hot (like too hot to keep touching).
Someone any ideas on this?
Thanks!
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Hey all, have any used Grbl and a functioning post processor for Fusion 360 for the MPCNC?
I believe the guffy PP also works for grbl.
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I use https://github.com/Strooom/GRBL-Post-Processor for grbl postprocessing in Fusion.
I also have an open PR to disable moving z to machine 0 at the start and end of the gcode (since my machine doesn’t have a z end stop it can’t know it’s machine coordinates)
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I am still having no luck with this. I completed my build and decided to get back to the Nema14 Current problem. First I thought my Rambo board was fried. The motor would not make noise, did not give torque, but did get hot. A regular Nema17 however functions normally on the same Z-output. Now I think my motor is dead. However when I measure the resistance of the coils it shows a 4.6 and 4.2 Ohms A little higher than my Nema17’s that show 2.8 and 2.8 Ohms on the coils. But that is probably because the Nema14 is much smaller. There is no cross-talk between the coils. Can a motor be defective, and still show this usual resistance?
Also there is definitely something ill on how the stepper current is set up in this firmware. I have been setting the current on the X and Y motors to 10 on both the cpu_map.h and config.h and there is no noticeable difference in torque afterwards. I suspect there is a fault in the firmware somewhere that keeps the motors running at max (or some pre-set) current, what will be no problem for most of the regular Nema17 motors.
I am experimenting firther without the Z-Axis. How do I disable the Z-axis in the homing sequence?
Just wanted to add, that I have used this GRBL from John on my MPCNC and it worked great. I thank you for that. Really liked the instant feedback and smooth operation. Not knowing, I had a mishap with one of my endstops, so I switched back to marlin thinking it was something else. I think I may revist this again. It has been sometime.
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Ok. I just flashed my board. Seems like it went through, although now I can’t get my machine to move! The LCD is obviously gone. All 5 steppers are locked in upon power up and got pretty toasty after me spending 20 minutes troubleshooting.
I was able to connect via Repetier Host, but no commands were going through. Do I need to change the configuration? I figured that gcode is gcode.
I also tried to connect via Easel, but all I got was a sequence of flashing yellow lights on the board in a sequence (R and then T). Also got this code that kept cycling from Easel’s machine troubleshooter but it doesn’t mean anything to me.
- portOpened
- [MSG:’$H’|’$X’ to unlock]
- Grbl 1.1k [’$’ for help]
- portOpened
What software is everyone using to control their machines?
What board and what firmware?
With GRBL I use universal gcode sender
RAMBo. Switched from Marlin to GRBL.
Thanks…will see if I can figure out universal gcode sender.
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ok…tried UGS. Installed on my Mac. Rebooted RAMBo 1.4 with GRBL. Tried many combinations of settings with USB port and baud rate. I was able to get a stable yellow “connected” light on the Rambo, but many times it just clicked and flicked the R/T yellow lights and kicked me off. The times I got what appeared to be a stable connection on the RAMBo, UGS didn’t appear to be fully connected and ready. The jog controls are greyed out boxes and not clickable.
Maybe I’m missing some configuration settings???
First suggestion try a new cable. I’m a windows guy and don’t have a RAMBO but used the mega GRBL x5 on ramps and it connected just fine.
Before you can move you have to click on unlock in the common actions tab
And under window. open console and see any errors and output
So I played around with the Baud rate a bit more. It connects at the 115200 setting. I was using 250000 on Repetier Host.
The thing is, it alarms when it’s connected. I can unlock (thanks for this tip), but when I try to jog the machine in the XY direction I get this error:
“[Error] An error was detected while sending ‘J=G21G91X1F10': (error:8) Grbl '’ command cannot be used unless Grbl is IDLE. Ensures smooth operation during a job. Streaming has been paused.”
When I try to jog the Z axis, I get a buzzing sound from the z stepper and no movement.
I got the same error it seems if you unlock again it clears it at least for me
First disconnect then reconnect and try again
The buzzing sounds like wiring or voltage on driver set to high
Now it’s just making that vibrating/buzzer sound anytime I hit jog. X, Y, and Z.
Doesn’t sound good. Almost like the steppers are locked and also trying to move at the same time.
That sounds like the voltage for the drivers is to high I’m not sure how to adjust that for the digipots but it should be in the firmware settings you flashed.
It can also be wired wrong pairs not wired together did you have it running before or just gettin GB goin GB n for first time?
I will see if I can find it
Thanks for the help. Yes, motor wiring and USB cable should all be good. Had been running for a couple months on Marlin.
The steppers are definitely very warm. Not sure if it’s a normal consequence of the GRBL firmware, but I don’t think the steppers were instantly locked when I fired it up on Marlin. I can hear them engage right after I fire up the board with GRBL.
No if they are hot it is a setting. Look for digipot setting in the firmware I can’t test anything reasonably in progress I want to get mine setup by tomarrow to test
The steppers will turn on immediate in GRBL and if you set $1 = 255 they don’t turn off till you tell them to
I remember a thread about the current setting. It was a $ setting. But it wasn’t clear it actually worked. Changing the starting setting in the firmware before flashing did.