Multimaterial Purge Calibration Tower

This is a set of purge calibration towers for testing the purge settings on multimaterial prints.

The Basic Idea
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It's important to find the right amount of material to purge when changing materials on a multimaterial print. Too much purge wastes material and takes extra print time. Too little purge leads to color bleeding.

These purge calibration towers let you test your purge settings for up to five materials at a time. For each material, the tower prints 5mm of a single material, then 5mm alternating between that material and another material, and finally 5mm of the new material. This lets you easily see if there's any color bleeding when the printer switches between the materials.

For towers with more than two materials, the segments are repeated so that every possible pair of materials is tested.

Four purge calibration towers are included:
* Purge Test 2A, 2B: Two materials
* Purge Test 3A, 3B, 3C: Three materials
* Purge Test 4A, 4B, 4C, 4D: Four mate