<p>You cannot drive the extruder unless you heat the nozzle to at least 170 °C, this is the default value in Marlin. This is to protect your printer from extruding at too low temperatures (which can harm your nozzle or extruder or grind the filament).</p>
<p>You can disable this feature by G-code using <a href="https://marlinfw.org/docs/gcode/M302.html" rel="nofollow noreferrer">M302</a>:</p>
<p><code>M302 S0</code> will disable the limit.</p>
<blockquote>
<p>always allow extrusion (disable checking)</p>
</blockquote>
<p>In Marlin, cold extrusion is prevented in the <code>Configuration.h</code> file:</p>
<pre><code>// @section safety

/**
 * Prevent extrusion if the temperature is below EXTRUDE_MINTEMP.
 * Add M302 to set the minimum extrusion temperature and/or turn
 * cold extrusion prevention on and off.
 *
 * *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
 */
#define PREVENT_COLD_EXTRUSION
#define EXTRUDE_MINTEMP 170
</code></pre>

CC BY-SA 4.0
2023-01-06T23:37:04.813Z
2023-02-06T09:20:01.407Z
2023-02-06T09:20:01.407Z
0scar
<p>I am building my own 3D printer and I finish almost everything the only thing that I can't solve is how to start the extruder stepper motor. I am using Pronterface and Marlin. I can't even make the motor rotate in Pronterface when I manually set the extruding temperature to 0 °C and then try to start the motor, it won't start.</p>
<p>What I tried so far:</p>
<ul>
<li>Changing to use drivers in Marlin</li>
<li>Testing drivers to see if they work</li>
<li>Testing the stepper motor to see if it works</li>
<li>Seting up Pronterface in different ways</li>
</ul>

<extruder><ramps-1.4>
Extruder MK8 won't turn using RAMPS 1.4 with Marlin
Aleksandar Milekic
# Extruder MK8 won't turn using RAMPS 1.4 with Marlin

(Asked by: username_0 on 2023-01-06)

I am building my own 3D printer and I finish almost everything the only thing that I can't solve is how to start the extruder stepper motor. I am using Pronterface and Marlin. I can't even make the motor rotate in Pronterface when I manually set the extruding temperature to 0 °C and then try to start the motor, it won't start.

What I tried so far:

* Changing to use drivers in Marlin
* Testing drivers to see if they work
* Testing the stepper motor to see if it works
* Seting up Pronterface in different ways

**Tags:** extruder, ramps-1.4


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## 1 answers

### Answer by username_1 on 2023-01-06. Score: 1

You cannot drive the extruder unless you heat the nozzle to at least 170 °C, this is the default value in Marlin. This is to protect your printer from extruding at too low temperatures (which can harm your nozzle or extruder or grind the filament).

You can disable this feature by G-code using [M302](https://marlinfw.org/docs/gcode/M302.html):

`M302 S0` will disable the limit.

> always allow extrusion (disable checking)

In Marlin, cold extrusion is prevented in the `Configuration.h` file:

```
// @section safety

/**
 * Prevent extrusion if the temperature is below EXTRUDE_MINTEMP.
 * Add M302 to set the minimum extrusion temperature and/or turn
 * cold extrusion prevention on and off.
 *
 * *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
 */
#define PREVENT_COLD_EXTRUSION
#define EXTRUDE_MINTEMP 170

```


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