<p>I am attempting to print a model that is too tall to print up-right and it has a large flat side that would be my first layer but ultimately would be the side of the object and I'd like it to look presentable.  I'm using wood PLA, so I intend to sand and stain it.</p>
<p>I've had no issues with adhesion when using a raft.  The slicer lays down a thick first layer that sticks beautifully.  Here's the first layer of a raft - nice thick lines:</p>
<p><a href="https://i.stack.imgur.com/2I1of.jpg" rel="nofollow noreferrer" title="First layer of a raft"><img src="https://i.stack.imgur.com/2I1of.jpg" alt="First layer of a raft" title="First layer of a raft" /></a></p>
<p>But when I try printing without the raft (even when using a brim) that first layer is not only thin, but easily moves away.  Also the lines meld together creating gaps in the layer. And that's no skirt around the outside, that's the side of the model that doesn't touch the fill.  I have to imagine this would be awful rough and impossible to sand out if it finished.</p>
<p><a href="https://i.stack.imgur.com/tFiqL.jpg" rel="nofollow noreferrer" title="Printing without a raft"><img src="https://i.stack.imgur.com/tFiqL.jpg" alt="Printing without a raft" title="Printing without a raft" /></a></p>
<p>By the second layer, the friction is picking up the first layer and it catches the extruder and bam:</p>
<p><a href="https://i.stack.imgur.com/hCaCe.jpg" rel="nofollow noreferrer" title="Destroyed second layer"><img src="https://i.stack.imgur.com/hCaCe.jpg" alt="Destroyed second layer" title="Destroyed second layer" /></a></p>
<p>I've done some research suggesting higher temps, both of the extruder and the plate.  I did see an improvement in the lines, but it still doesn't stick well.  And what is considered a good temp?  how do you know if you went too hot?</p>
<p>Any recommended settings in the slicer to make the bottom layer smoother?</p>
<p>The printer is a FlashForge Creator Pro.</p>

[{'answer_id': 18083, 'author': 'Kezat', 'author_id': 30645, 'author_profile': 'https://3dprinting.stackexchange.com/users/30645', 'pm_score': 2, 'selected': False, 'text': "<p>The motor is mounted in a fixed position no matter if it's on top or bottom.\nYou can imagine the lead screw as a rod hanging down and supporting the bed in the Z direction only, because all of the XY rigidity comes from the Liner rails the bed is attached to it works just as well if the stiff rod is under compression instead of hanging from the rod.</p>\n<p>Any forces that might &quot;pull it straight&quot; are the same forces that can cause Z wobble so you would not want to even try to use the misalignment to straighten a bent lead screw.</p>\n<p>The only thing this that really changes with this orientation is if the lead screw is under tension or compression. Even a relatively thin lead screw can easy counter the forces of gravity and the forces is the same in both directions. Its easy and cheap to make a smooth rod or rail straight but not so easy to make a threaded one straight.</p>\n"}, {'answer_id': 18086, 'author': '0scar', 'author_id': 5740, 'author_profile': 'https://3dprinting.stackexchange.com/users/5740', 'pm_score': 2, 'selected': False, 'text': '<p>No, but the answer could depends on how you set up the lead screws, what kind of lead screws are used and how they connect to the stepper. Also it is important how you transfer the linear Z motion into the X gantry.</p>\n<p>Note that regularly used TR08 (<a href="https://3dprinting.stackexchange.com/a/5668/">Trapezoid, 8\xa0mm</a>) lead screws are stiff enough to not flex under the limited load of an X gantry. So, putting them upright or down should not make a difference. Furthermore, the whole X-gantry is usually constraint in movement by the use of linear guide rods or rails.</p>\n<p>Note that lead screws are not perfect, certainly the cheaper versions (ball screws are better in that respect). The imperfections can cause the lead screw nut to move in the X-Y direction. If the nut is firmly attached to the X-gantry, this movement can be seen in the print like e.g. waves in Z-direction we call Z-wobble. There are designs like <a href="https://www.thingiverse.com/thing:2588347" rel="nofollow noreferrer">these</a> or <a href="https://www.thingiverse.com/thing:2910524" rel="nofollow noreferrer">these</a> to mitigate that problem. Leaving one end free (so not constraining both ends) of the lead screw is also a mitigation as with constraining both sides, you over-constrain the screw. Note that the spring couplers you see applied frequently are great for misalignment of stepper motor shaft and lead screw, but are detrimental for the Z-axis. When using such couplers for shaft misalignment, you should <a href="https://www.thingiverse.com/thing:2121687" rel="nofollow noreferrer">constrain at least motion in Z-direction</a>.</p>\n'}]
['https://3dprinting.stackexchange.com/questions/18090', 'https://3dprinting.stackexchange.com', 'https://3dprinting.stackexchange.com/users/31218/']