Learning Notes in 3D Printing Functional Parts

Wall (Perimeters) vs Infills

In every print, these two are a common settings to change but more so in functional parts. You'll almost always choose more walls than higher infills. So rather than 2 walls and 30 infills. It would be better to have 4 walls and just 10 infills.

Functionally, walls carry the load. When you apply stress to a part (bending, pulling, or compressing), the outermost layers experience the highest amount of strain.

Interestingly, walls are also much fast to print. Wall loops usually keeps the print head moving in a continuous loop, which is faster and cleaner for your printer's motion system.

Why not just choose more walls rather than higher infill everytime (even non functional parts)? Ah. Because not all models can have more walls, specially on the narrow parts (like a long thin tube). If you force it, the walls on the other side will collide with the wall on the other side. In this case, you are force to using lesser walls but with higher infill.

Can I just choose more walls and higher infills? Sure you can. The only caveat is efficiency. You'd be using more materials than needed and consequently more time.

Filament Material PLA vs PETG

You can definitely print functional parts with PLA but it is more limited to lesser load and tension. For example, missing remote control battery covers or even organisational containers like gridfinity.

But you will have more better mileage using PETG as it has more toughness and impact resistance. It also can be used longer in outdoors. So if you are printing water bucket for your plants, use PETG. PLA out in the sun will melt.