Getting the 3D print supports suitable for complex models is essential to printing success. When your model is not fully supported, the object may fall or fail. However, if the supports are too strong, they’ll be challenging to remove, and you might damage your model while trying to snip them off.
Here’s what to do when 3D print supports are too strong:
- Change the support settings.
- Use tree supports.
- Change the overhang angle.
- Adjust the support placement.
- Choose specific support structure shapes.
- Use a support brim.
- Design custom supports as part of the CAD model.
- Decrease the diameter of your points of contact.
So, let’s talk about how you can give your supports a clean cut. I’ll teach you some design methods to help you ensure that your supports are strong enough to keep your model up but not so strong that they won’t come off after the print job.
1. Change the Support Settings
Your support should be substantial enough to connect your model to the print bed, but it should only intersect with your model where it needs a crutch the most.
Increasing the perimeters of your support’s first layer can help you eliminate unnecessary contact points with your model, making them easier to remove in the end.
Adjusting the support settings in the following areas will help:
- The support roof
- The support floor
- First layer support
- Support interface
- Support infill
This YouTube video will help you adjust the settings for strong supports that snap off easily:
2. Use Tree Supports
If your supports are too tricky to remove, try switching up the type of scaffolding you are using.
Changing the standard supports to tree supports creates a smaller base like a branch on a tree. The smaller base means less surface to detach.
Tree supports offer several advantages:
- Tree support collision resolution reduces the possibility of collision with the model. Less contact means fewer places to disconnect.
- Tree support branch diameter places the touchpoints only at the base of the print, making them easier to remove.
- Tree support branch angle adjusts the maximum angle of each tree branch, allowing you to target the areas where your model needs the most support.
- Tree support branch distance places the branches at specific distances. Closer distances are harder to remove, while farther distances are easier to remove.
While tree branches are helpful since they offer minimal spots for removal, they are also tricky to design without creating overhangs. You will have to experiment with the settings to achieve the optimal gauges for your prints.
Utilizing tree branches can reduce print time, create fewer contact points, and use less filament, so they are worth investigating to see if they produce the ideal print supports for your models.
3. Change the Overhang Angle
While the standard assumption is that all features within a 3D print of more than a 45-degree angle need support structures, you can adjust this setting. Increasing and decreasing the angle can offer different contact points for support structures, and you might find one that works best for your print.
4. Adjust the Support Placement
The two selections for support placement are “everywhere” and “only touching the build plate.” The everywhere option will create supports in more locations, usually centered on a raft, causing you to address an increased number of blemishes post-printing.
If you choose “only touch build plate,” you will get a cleaner print, but your model could have some unsupported spots. Adjusting the support plate could produce a more pristine object than standard settings.
5. Choose Specific Support Structure Shapes
Of the five support structure shapes, lines and zigzags have the least infill, making them easy to remove. Of course, this also impacts their stability.
The triangle and grid shapes are the strongest with the most infill, making them the hardest to remove. The concentric form is a middle-ground choice that is neither difficult nor easy to snip off the print.
When you increase the support infill density, this makes a more rigid support shape. However, reducing the density produces a print that is easier to deal with post-printing if you don’t need a strong support shape.
Ultimately, the support structure shapes and density are worth adjusting to see if you can make a cleaner 3D print with fewer structures.
6. Use a Support Brim
The whole model can collapse when parts of your print are left unsupported. A small support brim will remedy this problem by using more filament on the inside structures. The support brim won’t make removal more difficult but will increase printing time and use more filament material.
Using other supports such as trees and geometric scaffolding with the brim can, however, eliminate the need for a raft, helping you use a bit less filament on supports.
7. Design Custom Supports as Part of the CAD Model
The way you connect your supports to your 3D model plays a huge role in how easy it will be to remove the scaffolding.
The print will have a clean interface and fully supported parts when incorporating the supports into the CAD design. There will be no missing sections if you create a separate STL file that fills the space between the print bed and the 3D model.
The dual extrusion merge function aligns the model and STL support files together. Here is the process:
- Create extrusions with Z-direction up to the base of the print.
- Leave the option to “merge/bodies feature” unchecked. This leaves the body as a separate model.
- Use the “combine subtraction” function to cut a cavity out of the supports.
- Choose only the underside bodies to save, as these are the supports.
- Save the Support Bodies as an STL file.
- Save the Model Bodies as a separate STL file.
- Import the files and choose “dual head printing with 2 colors/materials.”
- Save your model.
- Check the file in the Repetier Code.
- Load HIPS and ABS and print.
This link will help you design your custom supports:
8. Decrease the Diameter of Your Points of Contact
If your supports keep getting stuck to your prints, try decreasing the point of contact’s diameter.
When using scaffolding or trees, make the point of contact very small. Avoid intersecting your supports with your model too much. Ideally, your points of contact should be flush with the inside of your model for quick removal.
Choosing to use needle-thin supports can make removal more straightforward, but they will offer less support. So, when making thin points of contact, you might need to increase the number of supports that hold up your model.
Many 3D print users rely on the “enable support structures” and never attempt to refine the process. Learning the finer points of adjusting the settings will save printing time and produce less post-printing processing.
Using the right support type will produce a print with fewer points to detach. By customizing your support options with precise measurements, you can make less work for yourself on the backside of the printing operation.