<p>I am building a <a href="https://andypi.co.uk/2017/09/17/dolly-build-notes-prusa-i3-mk2-clone-3d-printer/" rel="nofollow noreferrer">dolly</a> and I am confused as to which proximity sensor to use. </p>

<p>Should I go for M8 or M12 and 5&nbsp;V or 6-36&nbsp;V? </p>

<p>What should be the best detecting distance? Should it be 2/4/8&nbsp;mm. Which one should I select?</p>

[{'answer_id': 5661, 'author': '0scar', 'author_id': 5740, 'author_profile': 'https://3dprinting.stackexchange.com/users/5740', 'pm_score': 3, 'selected': True, 'text': '<p>Tomas Sanladerer has produced a nice video on this topic: <a href="https://www.youtube.com/watch?v=il9bNWn66BY" rel="nofollow noreferrer">https://www.youtube.com/watch?v=il9bNWn66BY</a></p>\n\n<p>@ 7:31 you see an overview of the precision of various sensors, including the ones you mention. It appears that the M12-4 and M18-8 sensors are more accurate than the M8-8.</p>\n'}, {'answer_id': 5680, 'author': 'Matt', 'author_id': 6878, 'author_profile': 'https://3dprinting.stackexchange.com/users/6878', 'pm_score': 1, 'selected': False, 'text': "<p>As always cost will be a factor.  I found the M4 sensors to be be just not good enough, they have to be too close, and eventually it's going to catch on your print and damage sensor mounting and/or the hot-end assembly.</p>\n\n<p>The 8mm range sensors seem like a good distance, but you'll need to decide between a wider, heavier but cheaper model or the think, lighter more expensive model.</p>\n\n<p>If your goal is to optimise for speed, go the lighter version.</p>\n\n<p>In terms of sensing accuracy, if your layer height is typically 0.2mm then I don't think there's much point paying for more accuracy.</p>\n"}, {'answer_id': 6361, 'author': 'Shwans', 'author_id': 11297, 'author_profile': 'https://3dprinting.stackexchange.com/users/11297', 'pm_score': 1, 'selected': False, 'text': '<p>Duet3D has a very nice <a href="https://duet3d.dozuki.com/Wiki/Choosing_a_Z_probe" rel="nofollow noreferrer">overview</a>. It totally depends on your demands. e.g., accuracy, different build surfaces, tolerance. Personly I realy like the <a href="https://www.precisionpiezo.co.uk/shop" rel="nofollow noreferrer">piezo</a>. It actually uses your nozzle to \'touch\' the bed. So 0 height is absoluty 0. This eliminates the need for Z-offset.</p>\n'}]
['https://3dprinting.stackexchange.com/questions/5660', 'https://3dprinting.stackexchange.com', 'https://3dprinting.stackexchange.com/users/10117/']