Hello All,
First post here as new to the forum. I am having the exact same issue as Tom. My X and Y skip steps constantly. I also have the full RAMBO. All parts were bought from the store except for the 3d printed parts which i did myself. I was starting to think this machine was very weak but now I suspect a firmware issue. After 1 hour of running my motors are still cold to the touch, I mean cold, not even warm, the drivers are also still cold enough that I cant decide if they warmed up from when they were not running.
My axis will all move fine, but as soon as they are under load cutting material at only 20 speed the bit is able to move the DW660 on all 3 axis. The router goes wherever the bit wants it to. Often plunges down into the material. At this point the drivers and motors are all still cool to the touch. I read about other people having drivers overheat. Definitely not my problem.
I was looking into PWM_MOTOR_CURRENT to see if I could step it up. I have some experience programming in Arduino, but there’s still a lot I don’t understand. Above in the 16th post you can see #define PWM_MOTOR_CURRENT is commented out. Should it be? Or am I misunderstanding something. I just downloaded the newest Marlin-MPCNC_Rambo_T8_16T_LCD Firmware from Github and its exactly the same. Did someone accidentally disable the current control in a release?
I just found this post Regarding stepper motor driver current
Which suggests the setting to change is actually DIGIPOT_MOTOR_CURRENT
The current firmware I downloaded says:
#define DIGIPOT_MOTOR_CURRENT { 120, 120, 120, 120, 120 } // Values 0-255 (RAMBO 135 = ~0.75A, 185 = ~1A)
Since I am using RAMBO and everything is staying cold should I change the 120’s to maybe 165 and see what effect that has?