3D printing large parts can be tricky. Any imperfection can cause a failure of the whole assembly, which wastes time and filament.
The most important factor for any 3D model is bed leveling and Z axis offset.
Having the print head too low will cause it to drag the bed and make the stream too wide and thin.
Having it too high will cause the layer to not adhere to the bed.
If the bed is not level, likewise can apply in a constrained section of the bed.
Low spots are also a possibility – You may not be able to see 0.2 or 0.3 of a millimeter with the naked eye to recognize a low spot in the middle of the bed. That is a full layer thickness and can cause issues depending upon where the print head’s Z axis is calibrated.
Adding a BRIM is generally unnecessary with large parts, as they have enough interface surface area with the bed to stay in place. However, it can be implemented if that interface surface area seems insufficient.
Moderating the Print Speed is not as important on large parts, unless they have intricate details. In that case, it’s a judgmental call.
Wall or Shell Thickness is also less important for large parts, and can generally be left default unless other circumstances exist.
for large parts, Cooling is almost always off.
These are some rough starting points for settings:
- Parts 16-25 square inches (4″ x 4″ to 5″ x 5″):
- Brim off/optional
- Print Speed 30-40 mm/s
- Cooling OFF
- Parts 25-36 square inches (5″ x 5″ to 6″ x 6″):
- Brim off/optional
- Print speed 40-50 mm/s
- Cooling OFF
Two settings are shown below – One is slowed down for doing detailed parts such as curves and/or notches, one is “standard” speed. The standard speed is fine most of the time, but can cause loose strings or overshoots if there are alot of small details in an otherwise large part.
Slow / Safe settings:
Fast / Standard settings:
