Filament changer: several colours in one print

How a changer works

A printer with a changer has several spools alongside (up to 4 colours on ours). When the colour changes, the printer pulls the old filament out of the hotend back into the changer and feeds in the new one. The swap is computer-controlled and the whole process takes tens of seconds.

That is why the 3MF format matters in multicolour printing. The file records which part of the model has which colour, and the slicer turns it into a plan of swaps.

Why multicolour printing costs more

After a colour change, the hotend still holds some of the previous colour. It has to be pushed out away from the part, usually onto the wipe tower (purge). That plastic is paid for, but it never gets into the part.

Time also goes up with every swap. The more colour changes per layer, the bigger the tower and the more expensive the print. A design where colours change only once every several layers comes out cheaper than fine stripes.

How to order a multicolour part

• Send a 3MF. The colours have to be assigned in the file. There are details about the 3MF format and about our multicolour printing.
• Up to 4 colours. We cannot do more.
• Fewer transitions, lower price. Large single-colour areas are good value, while stripes and fine patterns are expensive.

What a changer cannot do

A changer is not magic: colours do not blend and transitions are sharp. Smooth colour gradients, photographs or raster images can therefore only be printed to a limited degree. Solid blocks of colour, lettering and logos look best.

Bear in mind too that each colour change can leave a small mark at the boundary. For lettering, allow for an accuracy of tenths of a millimetre. More practical tips on multicolour printing are in the separate entry.