Box w/ 3mm x 3mm magnet holes + printable inserts

I followed https://www.youtube.com/watch?v=0Sla-vIsvh4 to add a colored inlay to the box:

• Arrange both models in your slicer so that the inlay fills the void in the top
• Slice and print just the inlay. You might want to tweak your slicer settings to print a little slower for better build plate adhesion
• Once the first print is done, quickly start heating your build plate again to maintain adhesion
• Slice and print the top in the correct position. The inlay is 0.5mm. You'll want to set your z hop to (0.5mm - initial layer height + 0.1mm) so that the print head will clear the pre-printed inlay.