<p>I've recently switched to PETG , and I'm using Cura as slicer and Ender 3 as printer.</p>
<p>I'm printing a model which Cura declares to be <strong>35 g</strong>, but if I weigh the printed model it weighs <strong>23 g</strong>.</p>
<p>I'm printing with just 1 line of skirt, so its weight is negligible on total weight.
I've replaced the stock plastic extruder with a double gears metal extruder (3Dman 11 Dual Gear Extruder ).</p>
<p><a href="https://i.stack.imgur.com/22V5v.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/22V5v.jpg" alt="enter image description here" /></a></p>
<p>I've also replaced the stock springs with metals ones.</p>
<p>I'm not having a quality problem, just I want to understand if this difference is caused by a bad configuration that could be improved.</p>
<p>Which are the corrections/checks that I need to do in my setup (both printer and Cura) for fixing this difference?</p>

[{'answer_id': 16156, 'author': '0scar', 'author_id': 5740, 'author_profile': 'https://3dprinting.stackexchange.com/users/5740', 'pm_score': 2, 'selected': False, 'text': '<p>The density of the filament can be specified in the material model of the filament in Cura (Preferences -&gt; Configure Cura... -&gt; Materials and click on the material/filament you are using to slice your model for PETG), look at the value behind <em>Density</em>, the PETG filament I use is using 1.28 g/cm³ (<a href="https://colorfabb.com/petg-economy-black" rel="nofollow noreferrer">PETG Economy Black -&gt; Specification &gt;</a>).</p>\n<p><a href="https://i.stack.imgur.com/vy283.png" rel="nofollow noreferrer" title="Cura materials window"><img src="https://i.stack.imgur.com/vy283.png" alt="Cura materials window" title="Cura materials window" /></a></p>\n<p>This field is user editable, so you can change it to your needs. Cura calculates the weight based on the deposited volume.</p>\n'}, {'answer_id': 16158, 'author': 'R.. GitHub STOP HELPING ICE', 'author_id': 11157, 'author_profile': 'https://3dprinting.stackexchange.com/users/11157', 'pm_score': 2, 'selected': False, 'text': '<p>Likely underextrusion. The Ender 3\'s extruder is particularly bad at PETG and slips a lot unless you go really slow, like 3 mm³/s (about 40 mm/s at 0.2 mm layers and 0.4 mm line width) or lower.</p>\n<p>For a long time I thought this was a limitation of the material, at least without a really powerful hotend, and wondered why anyone liked it. But after replacing the extruder on my Ender 3 with one that grips the filament much better (among other differences) I can extrude at several times that rate with no extrusion issues.</p>\n<p>My extruder has a lot of differences from the stock Creality one that might be making a difference. It\'s (remote) direct drive, has a cut-out hobbed gear that wraps partly around the filament tensioned rigidly rather than with a spring, and has net 10:1 reduction gearing. I suspect the hobbed gear configuration makes the biggest different to increased PETG printing capability but I\'m not sure. Here\'s a picture of what I\'m talking about</p>\n<p><img src="https://i.stack.imgur.com/NxSQx.jpg" alt="hobbed filament gears" /></p>\n'}]
['https://3dprinting.stackexchange.com/questions/16155', 'https://3dprinting.stackexchange.com', 'https://3dprinting.stackexchange.com/users/27580/']