Stepper Motor does not have torque

Using Arduino Motors, Mechanics, Power and CNC
1

Hello everyone, I am writing to you because my stepper motor works without load perfectly but when it is opposed some resistance starts to jump

I attached an image so you can understand what I'm talking about
Simple program:

the vref is ok, the 24v power supply is stable and ok, the a4988 is ok, but this happens only whit this motor

#define dirPin 8
#define stepPin 7


void setup() {
pinMode(dirPin, OUTPUT);
pinMode(stepPin, OUTPUT);
digitalWrite(dirPin, HIGH);
}

void loop() {
digitalWrite(stepPin, HIGH);
delayMicroseconds(1500);
digitalWrite(stepPin, LOW);
delayMicroseconds(1500);
delay(10);
}

Stepper-motor-not-working.mpg (1.03 MB)

2

Looks normal for an overloaded step motor, post a link to the motor showing it's specifications, amps, torque, etc.
Do you have the current limiter on the driver set correctly for that motor?

3

Your image won't display - please post a JPG or PNG. See this Simple Image Guide

Can your motor move the load at a very low speed? A step every 13 millisecs is quite fast. Try 4 steps per second.

...R
Stepper Motor Basics
Simple Stepper Code

4

You know stepper torque drops off rapidly with speed? If you choose a motor based on its static, pull-out
torque, it will be far too weak for rapid movement. Good manufacturers will give torque/speed curves for
a motor at a variety of stepper-driver supply voltages.

5

Francisco-Colli:
Hello everyone, I am writing to you because my stepper motor works without load perfectly but when it is opposed some resistance starts to jump

I attached an image so you can understand what I'm talking about
Simple program:

the vref is ok, the 24v power supply is stable and ok, the a4988 is ok, but this happens only whit this motor

#define dirPin 8

#define stepPin 7

void setup() {
pinMode(dirPin, OUTPUT);
pinMode(stepPin, OUTPUT);
digitalWrite(dirPin, HIGH);
}

void loop() {
digitalWrite(stepPin, HIGH);
delayMicroseconds(1500);
digitalWrite(stepPin, LOW);
delayMicroseconds(1500);
delay(10);
}

This is the datasheet https://www.mitsumi.co.jp/latest/Catalog/pdf/motor_m49sp_2k_e.pdf

6

Robin2:
Your image won't display - please post a JPG or PNG. See this Simple Image Guide

Can your motor move the load at a very low speed? A step every 13 millisecs is quite fast. Try 4 steps per second.

...R
Stepper Motor Basics
Simple Stepper Code

its a video, i tried to attach it but i doesn't displays

i tried your solution, same issue

#define dirPin 8
#define stepPin 7


void setup() {
  pinMode(dirPin, OUTPUT);
  pinMode(stepPin, OUTPUT);
    digitalWrite(dirPin, HIGH);

}

void loop() {
    digitalWrite(stepPin, HIGH);
    delayMicroseconds(250);
    digitalWrite(stepPin, LOW);
    delay(250);
    
     digitalWrite(stepPin, HIGH);
     delayMicroseconds(250);
    digitalWrite(stepPin, LOW);
    delay(250);
    
        digitalWrite(stepPin, HIGH);
    delayMicroseconds(250);
    digitalWrite(stepPin, LOW);
    delay(250);
    
     digitalWrite(stepPin, HIGH);
     delayMicroseconds(250);
    digitalWrite(stepPin, LOW);
    delay(250);
  }
7

Francisco-Colli:
its a video, i tried to attach it but i doesn't displays

Put it on YouTube and post a link to the YouTube page.

...R