Understanding How Your Markforged 3D Printer’s Hardware & Software Components Contribute to its Performance
Minimum Feature Size is the 2nd of 3 in our series to understand how your 3D Printer’s hardware & software components contribute to its performance. Previously, we covered Layer Height, next up we’ll cover Precision and Accuracy.
Minimum Feature Size
Once you understand the impact of the nozzle on resolution and accuracy, another important topic to understand is the minimum feature size. Markforged mentions the XY resolution in their Composite Design Guide in the form of the XY minimum feature size. This value of 0.2 mm is the same for both desktop and industrial printers, since both use the same XY stepper motors. You can corroborate this resolution by modeling a small feature that protrudes or recedes into the wall of a print – try it!
0.2 mm emboss
0.2 mm recess
If we dial the size of the feature down to 0.1 mm, you can see that it still prints, but it requires a good bed level and proper belt tension to ensure the features appear. Anything less and the feature will blend into the wall of the print. To ensure your prints are consistently successful and of the highest quality, Markforged recommends that XY feature sizes do not fall below 0.2 mm.
0.1 mm emboss
0.1 mm recess
One note to avoid confusion – earlier, there was mention that nozzle diameter (bead width) can impact XY feature size. These features here are not as affected by nozzle diameter because they fall on the perimeter of the print – stepper motor precision has more of an impact here. Next, we will see an example where nozzle diameter has an impact on XY features.
From our examples comparing the resolutions on each axis, we can begin to see that 3D printers typically have higher resolution along the Z-axis than in the XY plane. Therefore, smaller features will have better finish when oriented on a vertical wall.
Take this grille-like embossed feature.- the grille ridges are 0.5 mm wide. If we print it in the orientation shown below, what can we expect the part to look like?
Where are my grille ridges?! How come it doesn’t look like my CAD file?
Remember, in the XY plane, we are limited by the nozzle diameter! Eiger registers 0.5 mm as too close to 0.4 mm to print consistently successful, so the slicer doesn’t recognize a feature here. In fact, Markforged’s Composite Design Guide suggests a minimum width of 0.8 mm for these ridges. Twice the nozzle diameter is a much safer bet!
Because Z-axis resolution is better than that in the XY plane, what if we changed the part’s print orientation?
Success! Printing at 0.1 mm layer height allowed each ridge to print with 5 layers. The entire grille is embossed 1 mm, 5 times greater than the 0.2 mm XY resolution mentioned earlier, so no problems here.