Shenzhen Alu Rapid Prototype Precision Co., Ltd.

A prime tower (also called a priming tower or ooze shield tower) is a small auxiliary structure that many slicers can automatically generate and print alongside your main model when you're doing multi-material or multi-color 3D printing with a single-nozzle printer (e.g., Prusa i3-style machines with an MMU, Palette, or similar filament-switching systems).

Why it exists

When you switch from one filament/color to another on a single-nozzle printer, some of the old filament remains inside the nozzle (this leftover material is called “ooze”).If you immediately start printing the new layer with the new filament, that leftover old color will smear onto your model for the first few millimeters → visible defects, color bleeding, strings, etc.The prime tower solves this by giving the printer a sacrificial object to print on right after every tool/filament change. The nozzle extrudes and wipes the old material onto the tower first, “priming” it with the new filament so that by the time it moves back to your actual model, the color is clean.

What it looks like

1.A thin, solid column or block (usually 10–30 mm wide) printed in every layer where a filament change occurs.

2.It’s placed somewhere on the build plate where it won’t interfere with your model (often in a corner).

3.It grows layer by layer, just like your model, but only gets printed on when a color change happens.

Common settings in slicers