Analysis of Layer Lines in 3D Printing

An intense curiosity to know about the calibration, metrics, printing techniques, and potential slicing errors was eating away at me.

So... I decided to examine the print lines myself with the help of a simple Chinese microscope—thanks a lot, China!!!; I was truly impressed by the print quality and the potential of these prints; for those curious about which printers were used in the experiment, they are listed in the materials (or supplies) list below.

Let's get started!!!!!!

For Step 1, we’ll be checking the results of slicing the head of Tony Stark from *The Avengers*—the franchise's genius, billionaire, playboy, and philanthropist.

It was sliced ​​using Lychee (simply out of personal preference), with the Halot R6 printer selected directly within the application's system.

In Step 2, the print lines of the Creality Ender 3 Pro printer were analyzed.

In addition to SLA and FDM printers, we will need to have a microscope with 1600x digital magnification on hand... Later on, I will share the software used and the calibration process!!!

1. The first step is to have the UniLab app/software for analysis!
2. Connect the digital microscope to your computer...
3. A calibration scale is included with the 1600x digital microscope; to perform the calibration, simply correlate the pixel ratio with the values ​​on the measurement scale!
4. After this process, perform a 1mm test measurement and check if the calibration worked as expected... in my case, it was 463 pixels, resulting in approximately 1.25mm on the scale (note: do not use a comma... the program doesn't recognize it—I admit I struggled quite a bit with this part)...
5. Then, once calibrated, I simply positioned it on the subject—in my case, Toninho's face—and pressed a capture button on the side; I had to reduce the lighting to get a sharper image on my computer screen.
6. As the photos show, my results ranged from 0.0550 mm to 0.0573 mm—an average of 0.0561 mm (or 56.1 microns), which is an excellent size!. I believe this demonstrates the capabilities of both the slicer and the printer.

1. For the FDM-based printer, the calibration process was maintained, yielding an analyzed value of approximately 1.008 mm.
2. However, what I observed is classic "squish" behavior: the base, where it contacts the printer's heated bed, shows dimensions close to the hotend nozzle size (0.4 mm), whereas the sides show dimensions matching what I programmed in the slicer (0.2 mm).
3. I obtained an average value along the Z-axis of approximately 0.2496 mm—very close to the 0.20 mm value set in the slicer—with a variation rate of roughly 24.8%!
4. At the base of the bed/PEI sheet, alternating values ​​of 0.2350 mm and 0.4355 mm were observed; measurements on the final print layer showed an average value of 0.3886 mm, whereas the expected value—based on the nozzle pressing the part against the PEI sheet—was 0.4 mm. This represents a 2.85% variation, which could be attributed to flow variables or even bed leveling.

Well, those were my observations regarding what I measured and was able to verify... I’m open to suggestions and further discussion.