Thanks to both you and Ryan. Hopefully, the new steppers will help us get to the cause. I will test and post again when they arrive.
You all have gone above and beyond.
Tom
The V1 Steppers arrived yesterday. They are now installed and the issue is resolved. X and Y move ok, Crazy. The V1s actually cost less than the Amazons that I was replacing. The leads to the Amazon steppers were lighter gauge wire, but, the steppersā weights were about the same. Everything was wired the same way, go figure! Unsolved mystery. Thank you for your time, advice and patience with me. I will update from the 402 and hopefully will be set.
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Can you measure the coil resistance of the bad steppers? Maybe they are high kv motors with lots of turns of thinner wire? Or do you have a link to the motors you bought?
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 thereās still a lot I donāt 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 120ās to maybe 165 and see what effect that has?
Just another note. I ran a estlcam file I created to shave 1mm off the top of my bed to level it. This file keeps running into the bed surface as Z drops so I put it 30mm in the air and put a stopper on the z conduit so it could not fall into the bed. I was re-testing the theory my drivers may overheat in time. I walked away for 1/2 hour and came back and the x axis was skipping steps under essentially no load.
I decided to try bumping those 120 values up and down a bit. I currently have set 170 on all and torque is greatly improved. doing a test and monitoring temperature. so far after 20 min the motors are just getting a little warm to the touch. Drivers are a little warm, but not at all hot.
Donāt do this. The router is 600W and has no idea what it is touching. The collet can easily start a fire and since everything is wood and plastic, and surrounded in sawdust, it would be a fireball in no time. It has happened.
Sounds like youāre getting there on the stepper current. You can set that with M907:
You need to use M500 to save it and it is a good idea to put it in your firmware file to save it if you need to flash it again.
I have a webcam pointed at the CNC and skype running set to auto answer. I have one account on the machine, and another I call it from which is my normal account. I was monitoring it from my computer as I was just inside. I can see if something catestrophic happens, but not missed steps.
I had seen those GCodes mentioned before but I didnt understand. So this is a way to adjust the current without having to reflash each time if I understand correctly. That would be helpful. Is there a code that will tell me what current is set to or actually present so I can confirm changes? Important note, I dont currently have a display. Forgot to add it to my order. Would be a lot easier than reflashing over and over.
Thanks,
M907 alone will report back the value, I think. Some commands donāt work that way though. M503 also prints a bunch of settings.