<p>I have a <a href="https://www.alunar.net/m508-self-assembly-3d-printer.html" rel="nofollow noreferrer">Alunar M508 machine</a> that I am trying to get new firmware on. The firmware that was loaded on the machine wasn't very good. The x axis was mirrored and the home point was way off. I was looking into Marlin to put on the machine, but don't have any experience on what to edit in the code to make it work for this machine. </p>

<p>Does anyone have any experience with this machine? Uploading new firmware that works or editing the code to make it work for this machine. I appreciate any help!</p>

<p>Here is a link to <a href="https://github.com/camalot/alunar-prusa-i3-marlin-i3-firmware" rel="nofollow noreferrer">the firmware I am currently using</a>. I'm on MacOS Sierra 10.12.5 using the 1.6.8 Arduino IDE.</p>

[{'answer_id': 5213, 'author': 'Ryan Conrad', 'author_id': 9543, 'author_profile': 'https://3dprinting.stackexchange.com/users/9543', 'pm_score': 0, 'selected': False, 'text': '<p><em>disclaimer</em>: I am the maintainer of the firmware that <a href="https://github.com/camalot/alunar-prusa-i3-marlin-i3-firmware" rel="nofollow noreferrer">you linked</a>. </p>\n\n<hr>\n\n<p>The firmware will not improve your print quality. well, it may to some extent, but for the most part, it wont. </p>\n\n<p>There is fine tuning involved that may be set for MY printer, but the values may need to be changed for you. Not to mention the physical tuning that I have done with my printer. Software is not the place to initially look for print quality improvements.</p>\n\n<p>Some examples:</p>\n\n<p>I printed anti-wobble caps for the Z-axis rods. Which improved the print drastically for me. As the print got higher, the quality got worse.</p>\n\n<p>I printed Z-stop improvements, so I could fine tune the Z-stop.</p>\n\n<p>I printed X &amp; Y belt tensioners. Loose belts cause skipped steps which causes poor quality prints. </p>\n'}, {'answer_id': 6081, 'author': '0scar', 'author_id': 5740, 'author_profile': 'https://3dprinting.stackexchange.com/users/5740', 'pm_score': 1, 'selected': False, 'text': '<p>The Alunar firmware you linked is a fork from the main Marlin firmware. If the bed Y direction is reversed, usually the stepper is incorrectly placed (mirrored) this is seen frequently for the Anet A8 printer which is very similar to your printer. In your case the X direction is wrong, this is usually related to the wiring of the stepper, reversing the connector by 180 degrees should do the trick (hardware solution). As a software solution, changing direction is not difficult in Marlin based firmware; you just want to invert the stepper direction; the following section in the configuration.h file does that for you:</p>\n\n<pre><code>// Invert the stepper direction. Change (or reverse the motor connector) if an axis goes the wrong way.\n#define INVERT_X_DIR false\n#define INVERT_Y_DIR false\n#define INVERT_Z_DIR true\n</code></pre>\n\n<p>Just change <code>INVERT_X_DIR</code> to <code>true</code>.</p>\n\n<p>If your home position is still not working for you, you should look into this section of the same configuration file:</p>\n\n<pre><code>// Travel limits (mm) after homing, corresponding to endstop positions.\n#define X_MIN_POS -33\n#define Y_MIN_POS -10\n#define Z_MIN_POS 0\n#define X_MAX_POS X_BED_SIZE\n#define Y_MAX_POS Y_BED_SIZE\n#define Z_MAX_POS 240\n</code></pre>\n\n<p>Change the <code>MIN_POS</code> positions as such that it starts at the corner of the bed. A more in depth bed center calibration tutorial can be found <a href="https://www.thingiverse.com/thing:2280529" rel="nofollow noreferrer">here</a>.</p>\n\n<hr>\n\n<p>P.S. Please <strong>do not print</strong> <code>anti-wobble caps for the Z-axis rods</code> (as mentioned in another answer), these are <strong>not reducing the wobble</strong>, in fact they cause problems. What happens if you constrain the top is that you get a <a href="https://en.wikipedia.org/wiki/Statically_indeterminate" rel="nofollow noreferrer">statically indeterminate construction</a>; forces and displacements are not predictable! Better solutions to eliminate Z-wobble are lifting devices that decouple X/Y movement from the threaded rod (eccentricity of the threaded rod) from the Z movement. Also fixate the threaded rod above the springy stepper-to-threaded-rod coupler.</p>\n'}]
['https://3dprinting.stackexchange.com/questions/4660', 'https://3dprinting.stackexchange.com', 'https://3dprinting.stackexchange.com/users/8529/']