LR3 Jerking

I have had a LR2 for years and used it for so many projects but when I converted to LR3 it cannot cut anything and this is my setting used on LR2 which worked fine


I am using TMC2209 I had the TMC5160 on my LR2

Is there anything I am missing in the software set up ?

Any help will be highly appreciated .

Hey Spino, a short video helps a lot when tackling problems like this, also, a picture of your build. Do you think it is rather software or hardware?

Sorry, not sorry…

That’s twerking, not jerking… -_-
Boomers, man…

Some days, I’m a boomer, some days, I’m gen-x. Also depends how the meds are hitting… :wink:

I drank from the garden hose, saw Donovan live, remember lawn darts, and used to mow my great grandmother’s yard with a rotary push mower (shik-a-shik-a-shik-a-shik-a-…).

I’ve also seen Black Flag in concert, the VHS-BetaMax wars (and known enough to have been disappointed in the outcome), been a member of Blockbuster Video, and still have an iOmega Zip and Jazz drive around here, somewhere.

I’ve watched c-beams glitter… wait, wrong memories… :unicorn:


I remember my dad choosing to get the VHS instead of betamax because the movie selection at sears had more VHS movies he liked than betamax had.

He bought the VHS and two movies that day.

oooooooooooooooooookay here are some pictures

Did you get TMC2209’s without pins already soldered on? Or maybe you’re a lot better at desoldering than I am lol. Hadn’t seen any missing the index pin and with yellow pin spacers like that.

I asked this because of belts etc., so the whole machine.

All three end mills I was using was done so I put in a new one and everything works ok but those stepper motors stall really quick .

I wish I can get a little bit more power out of the stepper motor I am using .

The current basically determines the torque.

The max current is set in the firmware. You can adjust it.

If the drivers get too hot, they will automatically adjust the current down. You want to avoid that. They will have to adjust themselves down below the safe max current to cool down. You can actively cool the drivers with a fan to get more current without them overheating. M122 will show you their OT prewarn status and the current they are set to.

If the motors get too hot, the plastic that holds them will get soft and they will deform. You don’t want that. If the motors stay under 50C, the plastic will be fine.

If the motors are moving fast (higher rpms) the voltage will drop. There is also voltage drop for long wire runs with skinny wires. If the voltage is not high enough, then you won’t get max current. This is a very specific problem when moving at high rpms. The easy fix is a 24V psu. But if you aren’t having this issue, it will be the same as a 12V psu.

I am currently using a 24v/6 amps psu and will the m122 give me realtime information when I am doing a cut to see my voltage, current and temp . Just to kind of see what is going on ,my table is only 3.5 feet wide so I can only imagine length of wire should not be an issue. I also notice the V1 shop has this for stepper motor Nema 17 76OZ/in Steppers, KL17H248-15-4A and I bought Nema 17 Stepper Motor Bipolar 2A 48mm 4-Lead on amazon . Will this make any difference with the issue I am currently having on my cnc ?

I don’t trust the ratings on stepper motors. They are a commodity to me. They are a coil of wire around a shaft, with some magnets in a case.

Judging by the stats, they should be fine. But the ultimate test is just adjusting the current and measuring the temperature of the motor. If your motor is too small, it will be hot, even at reasonable current levels.

The defaults in the firmware are trying to be low enough to not cause excess issues for people, while staying high enough to get things done.

I bet you find some extra room to tune them up. Even 50 or 100mA can make a big difference.

Thanks Jeff - where in the software (line ) can I change this current to R&D .

You can do it with gcode:

M906 X950

Will set the X drivers (I think both of them) to 950mA. That change will only be until the next reset. If you like the setting, you can save it to eeprom with M500.

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