<p>When printing objects higher than approximately 8-10&nbsp;cm, sometimes nozzle hits the printed model and knocks over it. After 7-8 hours of printing that's really annoying. I'm using Creality Ender 3 Pro with Ultimaker Cura. How can I avoid this problem?</p>

<p>As a note; it happens with thick, wide models without support structure too. I'm using Ender 3 Pro's stock magnetic bed.</p>

<p>Here are some photos of printed model.</p>

<p><a href="https://i.stack.imgur.com/0hIqg.jpg" rel="nofollow noreferrer" title="Failed print - photo#1"><img src="https://i.stack.imgur.com/0hIqg.jpg" alt="Failed print - photo#1" title="Failed print - photo#1"></a></p>

<p><a href="https://i.stack.imgur.com/HNiG4.jpg" rel="nofollow noreferrer" title="Failed print - photo#2"><img src="https://i.stack.imgur.com/HNiG4.jpg" alt="Failed print - photo#2" title="Failed print - photo#2"></a></p>

<p><a href="https://i.stack.imgur.com/Y841k.jpg" rel="nofollow noreferrer" title="Failed print - photo#3"><img src="https://i.stack.imgur.com/Y841k.jpg" alt="Failed print - photo#3" title="Failed print - photo#3"></a></p>

<p>I use Esun PLA+, the part was on baseplate without any loss of contact. It was like one layer missed its coordinates and then all corrupted.</p>

<p>I think it's not related with bed adhesion because for example for this model, it didn't knock over the model.</p>

<p>There is no roof for the model, I think it doesn't need any support structure. <a href="https://cdn.thingiverse.com/renders/35/b4/84/0c/45/74441e4966d7cc6caac1adbd2795375f_preview_featured.jpg" rel="nofollow noreferrer">Here</a> you can see the expected finished one: </p>

<p><a href="https://i.stack.imgur.com/U1nzR.jpg" rel="nofollow noreferrer" title="Expected finished print"><img src="https://i.stack.imgur.com/U1nzR.jpg" alt="Expected finished print" title="Expected finished print"></a></p>

[{'answer_id': 10301, 'author': 'Timm', 'author_id': 16792, 'author_profile': 'https://3dprinting.stackexchange.com/users/16792', 'pm_score': 0, 'selected': False, 'text': '<p>There are options in Cura to avoid that the extruder hovers over printed parts when traveling. There is also an option to lift Z axis while traveling. Those options are hidden by default. You can only enable them in advanced settings mode.</p>\n'}, {'answer_id': 10338, 'author': 'cmm', 'author_id': 2082, 'author_profile': 'https://3dprinting.stackexchange.com/users/2082', 'pm_score': 0, 'selected': False, 'text': "<p>There is a clear scar in the print that looks like the print head has hit it.  The scar is about 1/3 of the way up the straight return segment on the right side of the photo.</p>\n\n<p>The OP has provided enough information to show that it isn't an overhang or bridging problem.</p>\n\n<p>I don't see any cracks in the print where part of it may have separated and bent upwards.  I accept the OP's statement that the item is well attached to the bed.</p>\n\n<p>What problems could there be?</p>\n\n<p>The printer may have a Z-axis problem at that height.  Perhaps it exceeds the maximum Z-height, or perhaps there is some obstruction or debris in a lead screw that is preventing it from freely moving above that height.  The obstruction could be a cable that is too tight or an errant tie-wrap that hits something, or almost anything that interferes with motion at that height.</p>\n\n<p>There is always the possibility of a bad wire (such as to the nozzle heater) that causes problems when the height reaches a critical level.</p>\n\n<p>There may be a parameter change in the slicing software that is set for that height (or layer count).  There shouldn't be, but a default profile may have been changed.</p>\n"}, {'answer_id': 10389, 'author': 'she hates me', 'author_id': 16714, 'author_profile': 'https://3dprinting.stackexchange.com/users/16714', 'pm_score': 3, 'selected': True, 'text': '<p>It seems the problem was because of Z-axis leveling (level of the X-axis), I found out that the right side was more than 3-4&nbsp;mm below the left side when the Z-axis height exceeds around 8-10&nbsp;cm. Below 8-10&nbsp;cm, the two sides were even. I calibrated the X-axis by turning the eccentric nuts of the wheels and tighten them. I will try printing soon with some test objects.</p>\n'}]
['https://3dprinting.stackexchange.com/questions/10298', 'https://3dprinting.stackexchange.com', 'https://3dprinting.stackexchange.com/users/16714/']