Mari

What kind of infill is the best depends on the object/part that needs the infill... so there is no standard answer for your question!

@tim_t did you calibrate the extruder e-steps? First you have to have the hardware to work properly before you can start tweaking with software...

... instead of getting frustrated You should have remembered how you started printing with your ender 3... probably by using the Micro SD-Card...🤪 If you really, really, really need to print things, forget printing via USB and start with using the Micro SD-card... And @tinkergnome is right, use a dedicated print-server like octoprint, that is way, way better then using Cura for that!

Try another profile, maybe one of the settings has changed and therefore you have this strange behaviour... I don't get why you print a square around it... what's the purpose of that!

@ZachBrooks ... are you using a skirt, brim or raft? Object may fit the buildplate, but you need space for skirt/brim/raft... if not, then try rotating the object or scale it down By posting only the error-message we have no clue what you are trying to print or how the object is placed on the buildplate! @obewan, I wouldn't post a project-file of a bought STL-file... 🤪

to make it easier when using the rotate option, select the "select face to align to buildplate" option...

... Check this website, download the Gcode files and re-do you bed leveling... https://www.chepclub.com/bed-level.html After leveling the bed, calibrate your printer by printing Calibration-cube and also calibrate Extruder so it extrudes the right amount of material (you can find tutorials on YouTube). First make sure you can make descent prints with PLA before you start with PET-G... CHEP has also good profiles for Cura for your printer, download and Import them...

... Preferences... Profiles... Import... Wasn't that hard to find...

Press on the fx-icon in front of the Infill Line Distance value

A part of the object is not touching the buildplate... redesign, move it down into buildplate or flip it over...

Didn't know that there was a plug-in...

... I always keep a backup of the Gcode-files... so I store them locally and on my NAS! I also like to see what the printer is doing, so there is a webcam connected to the Raspberry 😉

When changing/inserting Mirco-SD card, use the "change SD-Card" option to read the content of the SD-card that is present! Long filenames can be a problem, so keep them as short as possible (like the suggested DOS 8.3 format). When a filename starts with "_" (underscore) this file will not show up on the printer... (found that out bij accident).

Connect to octorpint via your webbrowser, upload the file via the printer (you are able to choose where the file will be uploaded, internal SD of printer or SD of Raspberry). Sometimes it fails, then try again! What is the benefit of Cura uploading files to Octoprint? To use the Octoprint options you still have to make connection via Webbrowser!

I have only one printer, so I have no need to slice it for another printer and compare the amount of the material used and the printing time! I know calculations are not always that accurate... Compare ALL settings and maybe you find out why things are how they are! Hint: printing speed, travel et.c etc.

Did you check all other settings? There are many in Cura that can make things go faster or slower and need more or less material!

Some printers print fine without calibration, I noticed that my printer could use some calibration... When you are printing on the flexible magnetic buildplate, you better use 60 degrees to get good adhesion. Clean the buildplate with Isopropynol alcohol 70%... Printing temperature is depending on the filament type you are using (I print a lot with a PLA Filament from a Dutch Webshop 123-3D.nl. My ideal temperature for this filament is 210 degrees!) For calibrating X,Y and Z, you can print a calibration cube... You can find many tutorials on calibrating your printer on YouTube, for example on the channel of CHEP!

I almost ran out of filament, so only printed 50% of the object. The problem were the poor result of the printed pegs. Like you can see, this is a good print of the pegs... I did a little search on the WWW, Print Temperature of Inland PLA+ should be 205-225 degrees, so if you print this on a too low temperature you get bad prints! Find out what the best print temperature is for this type of filament on your printer (not every printer is the same, so ideal print temperature may differ a few degrees between Ender 3 pro and another Ender 3 Pro). Did you calibrate extruder, X,Y and Z steppermotors? You will be surprised to see that and Ender 3 Pro needs calibration, you probably print with standard E-steps setting in Firmware!

Just downloaded your 3MF-file... Starting the print with only minor changes on your settings (Buildplate 50 instead of 60 degrees, Printing Temperature 210 instead of 200 degrees and brim instead of skirt for beter printbed adhesion!)... Will show later how the prints looks like! Did you print it in this orientation? With the pegs-side on the heated bed? Not sure it will print that way without support... Will see, printer is running!

Happy Printing...

You're right... It must be SAVE not EXPORT...

Save as 3MF, then we have not only the object but also your printer profile and other settings...

In the materials settings I have set the temperature on that the filament type prints the best on my printer, so for PLA I have set it to 210 and for TPU to 235...

When you switch from material A to material B, the "default" printing temperature don't have to be the same... For example, I print PLA on 210 degrees and TPU on 235 degrees... When I switch material from PLA to TPU the nozzle-temperature changes automatically! I have set both temperatures in the material-setting! The only thing I have to remember is to switch material when I switch filament 😉

To solve possible problems, we need more information than you are giving us... You only tell us the printing temperature, the type of filament, layerheight, infill percentage, support... but Cura has many more settings... Next time EXPORT the object you want to print as 3MF-file, so we have not only the object but also your printer profile and the settings! It seems there is no problem with the object you want to print...