<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>

The density of the filament can be specified in the material model of the filament in Cura (Preferences -> Configure Cura... -> Materials and click on the material/filament you are using to slice your model for PETG), look at the value behind
Density
, the PETG filament I use is using 1.28 g/cm³ (
PETG Economy Black -> Specification >
).
This field is user editable, so you can change it to your needs. Cura calculates the weight based on the deposited volume.