<p>When I adjust the probe offset to get the proper layer height and adhesion, one side is set right but the other doesn't work. If I decrease the probe offset (say -1.100 to -1.050) the right side seems to print better; if I increase the probe offset (-1.050 to -1.125) the left side will adhere to the plate properly.</p>

<p>Before I added the BLTouch and upgraded the firmware to Marlin 1.1.9 I was able to print a perimeter square (with a little manual adjustment).</p>

<p>My Printer is the Ender 3 and I am using a <a href="https://www.amazon.co.uk/Comgrow-Glass-Creality-Printer-Ender-3/dp/B07DSC9TJQ" rel="nofollow noreferrer">glass bed</a> and the model is this <a href="https://www.thingiverse.com/thing:2280529/" rel="nofollow noreferrer">centre crosshair</a></p>

<p><a href="https://i.stack.imgur.com/xVVfi.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/xVVfi.jpg" alt="enter image description here"></a>
<a href="https://i.stack.imgur.com/pBFny.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/pBFny.jpg" alt="enter image description here"></a>
<a href="https://i.stack.imgur.com/Y0usO.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Y0usO.jpg" alt="enter image description here"></a>
<a href="https://i.stack.imgur.com/JECOP.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/JECOP.jpg" alt="enter image description here"></a></p>

[{'answer_id': 7413, 'author': '0scar', 'author_id': 5740, 'author_profile': 'https://3dprinting.stackexchange.com/users/5740', 'pm_score': 3, 'selected': True, 'text': '<p>I have had exactly the same experiences as you did with a inductive sensor on a Prusa i3 clone. It looks as though the bed leveling is not executed, or the level/mesh tilted. Please do note that automatic bed leveling is <strong><em>not magic</em></strong>, you still need to provide a <strong><em>build platform as level (and flat) as possible</em></strong>. A slate of glass is a good build platform surface as the glass production process ensures that the glass is very flat and easy to level.</p>\n\n<p>What I did to solve the problem is that I re-leveled the bed and send the <a href="https://reprap.org/wiki/G-code#M420:_Leveling_On.2FOff.2FFade_.28Marlin.29" rel="nofollow noreferrer"><code>M420 S1</code></a> command over USB to the printer to enable bed leveling as I was under the impression that it did not use the grid obtained with <code>G29</code>.</p>\n\n<p>On my CoreXY I also use a touch sensor (3DTouch, which is a BLTouch clone) like you do, even with that sensor I sometimes see that the automatic level is uneven (one side of the skirt has very thin/see through deposition, while the other side appears normal), this is most probably caused by the sensor accuracy (or an obstruction under the probe needle). There is a way to increase the probing accuracy by using double probing where the second probe is advancing slower to the build platform as can be seen in the Marlin Configuration.h file:</p>\n\n<pre><code>// Feedrate (mm/m) for the first approach when double-probing (MULTIPLE_PROBING == 2)\n#define Z_PROBE_SPEED_FAST HOMING_FEEDRATE_Z\n\n// Feedrate (mm/m) for the "accurate" probe of each point\n#define Z_PROBE_SPEED_SLOW (Z_PROBE_SPEED_FAST / 2)\n</code></pre>\n\n<p>For double probing you require to set:</p>\n\n<pre><code>// The number of probes to perform at each point.\n//   Set to 2 for a fast/slow probe, using the second probe result.\n//   Set to 3 or more for slow probes, averaging the results.\n#define MULTIPLE_PROBING 2\n</code></pre>\n\n<hr>\n\n<p><em>Side note:<br>\nFrom an earlier posting it appears that you are using the <code>#define Z_PROBE_OFFSET_FROM_EXTRUDER</code> in the configuration file to set the offset. It is much more convenient to set that through the <a href="http://marlinfw.org/docs/features/lcd_menu.html" rel="nofollow noreferrer">LCD menu</a> (<code>Bed Leveling</code> -> <code>Z Probe Offset: -–-</code>) or send  the <code>M851 Zx.xx</code> directly over USB or load through a .gcode file from SD card to prevent numerous flashing the firmware with alternative parameters. Make sure that you enable:</em></p>\n\n<pre><code>#define EEPROM_SETTINGS // Enable for M500 and M501 commands\n</code></pre>\n\n<p><em>in the Configuration.h file and execute <code>M500</code> to store the new setting set by <code>M851</code>.</em></p>\n'}, {'answer_id': 7423, 'author': 'Siebrand', 'author_id': 13480, 'author_profile': 'https://3dprinting.stackexchange.com/users/13480', 'pm_score': 0, 'selected': False, 'text': '<p>From the looks of your test print, this is unlikely all or only due to levelling unless the glass plate is abnormally uneven. You may have to check your extrusion (speed, temp, feed) parameters and/or adhesion (clean with aceton and/or prepare with hairspray or glue stck)</p>\n'}]
['https://3dprinting.stackexchange.com/questions/7412', 'https://3dprinting.stackexchange.com', 'https://3dprinting.stackexchange.com/users/13327/']