Single colour vs multi material printing: which should you choose
Quick answer
Print single colour by default, on a machine such as the Creality Ender 3 V3 SE ($186.14): it uses only the filament the part actually needs, with none lost to purging between colors. Choose a multi material printer, such as the ANYCUBIC Kobra X Multicolor ($329.99) with native four-color capability, specifically when the part needs multiple colors or materials in the same print, and go in accepting that the purge tower flushed between every color change is sacrificial filament that on small multi colour prints can use more material than the part itself.
Creality Ender 3 V3 SE Beginner-Friendly 3D Printer with Auto Leveling
most parts, and anyone who wants zero purge waste
| Single colour | Multi material | |
|---|---|---|
| Filament waste | None beyond normal supports | Purge tower flushed between every color or material change |
| Purge waste on small prints | Not applicable | Can exceed the weight of the part itself |
| Printer complexity | Simpler, one filament path | Multiple filament paths or a filament changing unit |
| Print time | Faster for a given part | Slower, due to purging and tool changes |
| Best for | Most parts | Parts that need real color or material combinations |
| Cost driver | Just the part material | The purge tower, not the machine price |
What actually happens inside a multi material printer when it changes color?
When a multi material printer switches from one filament to another mid-print, it has to purge the old color out of the nozzle and hotend before the new color is clean enough to print with. That purged filament is extruded somewhere off to the side of the actual part, onto what is usually called a purge tower or prime tower, and then discarded once the print is done. It is sacrificial material with no other purpose than clearing the nozzle for the next color.
Can a purge tower really use more filament than the part itself?
Yes, and this is the real cost of multi material printing that the machine price does not capture. On a small print with several color changes, the purge tower has to be built up through every single change, and for a physically small part, that accumulated purge material can outweigh the part. A large single color print barely notices its purge waste as a fraction of the total; a small trinket with five color swaps might spend more filament clearing the nozzle than it spends on the object.
This means the real cost driver of multi material printing is not the printer price, it is how many color or material changes a given design requires relative to its own size.
Does single colour printing waste any filament at all?
Single colour printing is not entirely waste free, since most prints still use some support material, but that waste is typically a small fraction of the part and can often be minimized or eliminated with better orientation. There is no equivalent to a purge tower, since there is no color or material change happening mid-print, so the filament loaded is filament that either becomes the part or a minor amount of support.
How can I reduce purge waste if I do want multiple colors?
Designing with fewer total color changes per print, grouping features by color rather than alternating repeatedly, and printing larger batches of the same multicolor design at once so the purge cost is spread over more finished parts are the practical ways to bring the purge tower cost down relative to what you get out of it. None of these eliminate the purge tower, but they reduce how often it has to run per part produced.
When is multi material printing worth it despite the purge waste?
When the part genuinely needs the color or material combination to do its job or look right, such as a sign with multiple colors, a part combining a rigid material with a flexible one, or a display piece where single colour would defeat the purpose. For purely functional parts where color does not matter, or where a single color adequately represents the design, the purge waste is a cost with nothing to show for it, and single colour printing is the better choice.
Multi material printing
Anycubic Kobra X Multicolor 3D Printer, Easy Setup, Native 4-Color
parts that genuinely need multiple colors or materials in one print
Both sides of this comparison
- ELEGOO
ELEGOO ABS 3D Printer Filament 1.75mm Black 1KG Strong Layer Adhesion
$16.99 Check pricePrices change often - Polymaker
Polymaker ABS Filament Black 1KG 1.75mm, Heat Resistant, Strength
$17.10 Check pricePrices change often
Common questions
Does every multi material printer waste filament on a purge tower?
Any printer that changes filament color or type mid-print needs to purge the previous material out of the nozzle before the new one prints cleanly, and that purged material has to go somewhere, which is the purge tower. Some systems are more efficient than others at minimizing how much gets purged per change, but none eliminate it entirely.
Is multi material printing only about color, or does it include different filament types?
Both. Multi material printing covers pure color changes within the same material as well as combining genuinely different filaments in one print, such as a rigid body with a flexible section. The purge tower cost applies to both cases, since the nozzle has to be cleared any time the extruded material changes, regardless of whether that change is a color or a material type.
Why does a small multicolor part sometimes cost more in filament than a larger single color one?
A small part with several color changes accumulates purge waste through every single change, and that waste does not shrink with the part size, it depends on the number of changes. A larger single color part has no purge waste at all, so even though it uses more filament for the part itself, it can end up using less total filament than a small, frequently color-changed print.
Can I avoid the purge tower entirely on a multi material printer?
Not entirely, since some purging is required any time the nozzle needs to run a new color or material cleanly. You can reduce the total amount by minimizing the number of color changes in a design and by grouping colors so the printer switches less often, but a fully purge-free multi material print is not realistic on most consumer systems.
Should a beginner start with a single colour printer or a multi material one?
Single colour. It is simpler to operate, has no purge waste to plan around, and lets you learn the fundamentals of printing without an extra variable. Move to a multi material printer once you have a specific design that needs multiple colors or materials and you understand the purge tower cost you are taking on.