I’m just starting multi-color printing. Currently printing some small bins. The first 11 layers are white and starting at the 12th layer it is black.
I know settings can be turned on/off in the “others” tab. And I could possibly turn off the prime tower completely for my situation. But understanding these questions would be helpful:
The very first thing that is printed is the base layer for the prime tower - is that to make sure no other color is present? Even if this is because my previous print was a different color (in this case it was but my P1S has been powered off anyhow the past 18 hours) this isn’t an issue if I print something that is one color. No prime tower is needed.
2 . My print keeps adding to the prime tower in between layers even before it has switched to my different color? Why would it do that?
3 . What’s the point of a brim in the prime tower, or any other seemingly cosmetic function I would change - ribs, infill gaps, etc.?
A prime tower shouldn’t be present if you are printing in only one color. If you are seeing one anyway, it’s possible that time-lapse is enabled.
The prime tower is used on the layer in which a color change takes place. For this reason, it must be printed along the way so that it’s high enough when needed. Otherwise, if the prime tower was not gradually built up, when changing colors the bed would have to raise to that initial position - this would either cause risks of the toolhead colliding with taller prints or effectively reduce your printable area on the plate significantly to eliminate the chance of collisions.
The brims on the prime tower are not cosmetic but stabilize it (being a tall, thin structure) so that it won’t be knocked over.
Slicing logic is fairly complex, especially on modern printers that have a lot of fancy hardware. That being said, this is my best guess to each of your points.
Your nozzle will be purged before it starts a new print. Why not use some of this material that will be purged anyway to print the base of the prime tower? It saves filament.
Same as my answer to 1, the layer on the prime tower needs to be printed regardless, maybe not all of the previous filament was meant to go out as purge poop.
Prime towers get knocked over all the time, having a brim is very much needed. I have no idea about the other settings, maybe it’s simply to give the user more options rather than no options, i.e. some infill patterns are more prone to collisions.