Support Filament
Posted: Sun Sep 13, 2026 11:34 pm
One of the huge benefits of multi-toolhead printers is the option for printing support in a different material from the main filament. That means, for example, PETG for the printed object and PLA for the support. They don't stick together very well, so the Z gap can be reduced to zero (improving quality), and the support breaks off cleanly. Another idea is to use PVA for support, and then dissolve it away afterwards in water (but I have not tried that).
As great as this sounds, there are more wrinkles to overcome than at first meet the eye:
Firstly, incompatible filaments are just as much a curse as a boon. Printing onto the support needs a bit of stick, just the same as you need stick on the print bed. You have to be able to draw onto the support without it peeling off, and if the slicer decides to start the layer over support rather than body, that's a recipe for disaster.
Multi-toolheads (or even single toolhead with an AMS) means the slicer adding a prime (or wipe) tower to the print, This builds alongside the print so there's somewhere to wipe each nozzle before it starts the layer, having oozed a bit while the other toolhead was printing. This is fine for multi-colour (same material), but for muti-material the prime tower isn't well designed (at least, not in Orca) for the same reason as in the previous paragraph – the prime tower alternates layers of different materials, and it is unstable. If the prime tower fails (which becomes increasingly likely the taller the print), the main print becomes messy and may fail. This could be solved if there were separate prime towers for each material, although separate interlocking parts to one prime tower might be better.
Because swapping filament in an AMS system takes a lot o time and wastes a lot of filament, Orca defaults to only using the support filament for the interface layer between support and model, which in most cases will reduce the swaps substantially. However, the interface layer then sticks to the model just as well as it sticks to the rest of the support, and I found it tricky to remove when it is such a thin layer. I find it better to print the whole support in the support filament, which is an option in Orca. That way, the whole support breaks away without leaving the interface layer behind.
As great as this sounds, there are more wrinkles to overcome than at first meet the eye:
Firstly, incompatible filaments are just as much a curse as a boon. Printing onto the support needs a bit of stick, just the same as you need stick on the print bed. You have to be able to draw onto the support without it peeling off, and if the slicer decides to start the layer over support rather than body, that's a recipe for disaster.
Multi-toolheads (or even single toolhead with an AMS) means the slicer adding a prime (or wipe) tower to the print, This builds alongside the print so there's somewhere to wipe each nozzle before it starts the layer, having oozed a bit while the other toolhead was printing. This is fine for multi-colour (same material), but for muti-material the prime tower isn't well designed (at least, not in Orca) for the same reason as in the previous paragraph – the prime tower alternates layers of different materials, and it is unstable. If the prime tower fails (which becomes increasingly likely the taller the print), the main print becomes messy and may fail. This could be solved if there were separate prime towers for each material, although separate interlocking parts to one prime tower might be better.
Because swapping filament in an AMS system takes a lot o time and wastes a lot of filament, Orca defaults to only using the support filament for the interface layer between support and model, which in most cases will reduce the swaps substantially. However, the interface layer then sticks to the model just as well as it sticks to the rest of the support, and I found it tricky to remove when it is such a thin layer. I find it better to print the whole support in the support filament, which is an option in Orca. That way, the whole support breaks away without leaving the interface layer behind.