3D printing support materials - A guide for better results
When 3D printing complex parts, overhangs or geometries with ”hanging” parts, support materials are often needed. supports) to allow the printer to build up the object layer by layer. The support material acts as a temporary structure that stabilizes and supports the print, and is removed afterwards. Here we look at the different types of support material, how best to use them and what techniques are available to simplify post-processing.
Why are support materials needed?
3D printers working with FDM/FFF technology melt plastic wire and lay it down layer by layer. If a part of the model is very cantilevered or has a cavity in the air, it will be difficult for the molten plastic to adhere without a support. The support material then acts as a temporary platform on which the plastic can be laid, for example:
- Overhang which is steeper than about 45° from the vertical.
- Bridges or piers that spans a wider range.
- Cavities or undercut areas that cannot be written ”on top” of previous layers.
Using support materials allows you to print more complicated and detailed models.
Types of support material
Same material as the main printout
If you are using a simple FDM printer with only one nozzle, the printer can build supports out of the same plastic (PLA, PETG, ABS, etc.) as the rest of the model.
Advantage: No extra material costs, easy handling.
Disadvantage: Can be more difficult to remove and sometimes leaves marks or damage to the finished part.
Water-soluble support material
Dual-nozzle printers can combine a main material (e.g. PLA) with a separate, water-soluble material such as PVA or BVOH.
Once the printing is complete, the part is placed in water, where the support material dissolves.
Advantage: Minimal marks after the supports, ideal for advanced geometries with hard-to-reach spaces.
Disadvantage: More expensive and sensitive filament, usually requires humidity protection and a printer with multiple extruders.
Chemically soluble support material
Here a plastic is used that dissolves in a specific solvent, e.g. HIPS in limonene if the rest is ABS, or ESM-10 in alkaline baths if the rest is Nylon.
Advantage: Ideal for industrial applications where precise and clean geometry is needed.
Disadvantage: Requires handling chemicals and special equipment to dissolve the supports safely.
How to choose the right settings for support in your slicer
Most slicer programs (Cura, PrusaSlicer, Simplify3D, etc.) offer a range of settings for support materials. Some important parameters:
Support structure (Typical structure):
Grid/rectilinear - ”grid structure” that is often stable and relatively easy to remove.
Tree supports (tree structure) - branches upwards towards the overhang, saving material and facilitating removal. Mainly available in some slicers, e.g. Cura.
Support density (Density):
Higher densities provide more stable support and a better surface on the underside of the part, but require more material and can be more difficult to remove.
Lower densities reduce material consumption and may be easier to remove, but risk providing less support to thin or large overhangs.
Distance between support and detail (Z-distance and XY-gap):
A small gap brings the top surface of the support closer to the model and provides a finer finish, but may stick hard or leave marks.
A slightly larger distance simplifies removal but may impair the surface against the overhang.
Overlap and contact method (Interface layers):
Some slicers allow a separate layer between the support material and the model, called an ”interface” or ”breakaway interface”.
This layer can be denser or printed in a different material for easier removal.
Partial setting
Often, you can manually choose where to place supports in the slicer. You may only need supports in critical places, not the whole model.
This saves material, printing time and simplifies post-processing.
Tips for easy removal of supports
- After heating: Removing the supports shortly after the model is ready (and slightly cooled, but still not completely cold) can make the plastic more pliable.
- Tools: Use a slotted screwdriver, pliers or a small knife to gently pry the support loose. Think about safety!
- Grinding and polishing: If small residues of support material remain, you can use fine sandpaper or a file to smooth the surface.
- Water soluble: In the case of PVA or BVOH backing, it is sufficient to soak the part in water for a few hours. You can then brush off the last remnants with a soft brush.
- Chemical solution: For HIPS as a support material, dissolve in limonene, and for ESM-10 in alkaline baths. Always follow safety instructions carefully.
Common problems and solutions
Too much aid:
The problem: Unnecessarily long printing time, high material consumption and difficult removal.
Solution: Reduce support density, use tree stands or place supports only where they are really needed (manual support placement).
Too little support:
The problem: Poor quality of overhangs or completely failed bearings.
Solution: Increase the support density or change the angle of overhang in the design to reduce the need for support.
Damaged detail area:
The problem: The support is too tight, leaving marks or dragging parts of the model.
Solution: Increase the distance (Z-gap), reduce the support density or use separate interface layers for easier removal.
Too long printing time:
The problem: A lot of support material can drastically increase printing and post-processing time.
Solution: Review the orientation of the model. Sometimes a different position on the building plate can reduce the need for support. Also test tree stands or lower the support density.
Executive summary
Support materials are a necessary part of 3D printing to create detailed and advanced models. Understanding which support material and settings are best suited for your part will help you:
- Reduce the risk of failed overhangs.
- Improve the surface finish.
- Get easier and faster post-processing.
Experiment with different types of supports, both in terms of materials and slicer settings. Try everything from simple grid structures to tree supports, and consider how you can orient the model to minimize the need for supports. In this way, you will create an efficient printing process with the best possible end result.