<p>On a Creality CR-10 Max, there is a bag of unidentified spares, which include three unmarked nozzles.</p>
<p>There is a needle that is exactly 0.4 mm in diameter, which needle fits exactly inside one of nozzles. It also fits loosely in the largest nozzle, which diameter looks like it's really close to 0.8 mm on my digital caliper. The smallest one has only room for the tip of the needle, and the digital caliper reads 0.34 mm on the tip of the needle when pushed from the inside of the nozzle.</p>
<p>I assume the sizes are: 0.8 mm, 0.4 mm and 0.3 mm.</p>
<p>Can you tell me how to measure the diameter with better accuracy?</p>

[{'answer_id': 14045, 'author': '0scar', 'author_id': 5740, 'author_profile': 'https://3dprinting.stackexchange.com/users/5740', 'pm_score': 2, 'selected': True, 'text': "<p>I've designed similar sensor casings, sometimes the filament catches a ridge/ledge or part of the cavity, even when it is chamfered or rounded. The arm of the limit switch pushes the filament up, away from the filament straight path.</p>\n<p>Have you tried cutting the filament under a very sharp angle, that may work.</p>\n"}, {'answer_id': 18349, 'author': 'alecail', 'author_id': 18571, 'author_profile': 'https://3dprinting.stackexchange.com/users/18571', 'pm_score': 0, 'selected': False, 'text': '<p>Here is 3D model that better explains why it was catching and how to remedy the problem:</p>\n<p><a href="https://i.stack.imgur.com/ooe48.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ooe48.png" alt="enter image description here" /></a></p>\n<p><a href="https://i.stack.imgur.com/dTy92.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/dTy92.png" alt="enter image description here" /></a></p>\n<p><a href="https://i.stack.imgur.com/m4Y91.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/m4Y91.png" alt="enter image description here" /></a></p>\n<p><a href="https://i.stack.imgur.com/Pv4Op.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Pv4Op.png" alt="enter image description here" /></a></p>\n<p>The filament is likely to have some twists and the bevel you create may not be in the correct orientation once it catches the ridge.</p>\n<p>The out hole is not chamfered on the inside, as it is drilled from the outside, and I guess a chamfer on the inside is not available at this price range.</p>\n<p>I found that twisting the filament 90° at most one way or the other always helps the filament finds its way. It can be tricky because of the small diameter/stiffness of the filament, with the spool still attached to the other end.</p>\n'}]
['https://3dprinting.stackexchange.com/questions/14095', 'https://3dprinting.stackexchange.com', 'https://3dprinting.stackexchange.com/users/18571/']