Inferior Surface Quality underneath Supports
What Is It?
With extreme overhangs, you need to use support structures that use the print's surface as their base. In such cases, the support pillars can adhere firmly to your print, affecting your part's surface quality. Less distance between the support base and the print can make removing the supports a challenge.
Popular slicers such as Cura and PrusaSlicer circumvent this issue using Tree Supportstructures. Tree supports have minimal contact with your 3D prints and help you achieve better-looking parts even with large overhangs.
What To Check?
- Support settings
- Print Geometry
How To Fix It?
Adjust the Bottom Support Z-distance
If the support pillars are too close to your print's surface, these will adhere firmly and leave marks once you remove them. In contrast, if the distance between the top of your print and the bottom of the supports is high, the support will not have a good foundation. The support pillars might fail in such cases resulting in the loss of a base for your overhangs.
It's essential to calibrate the bottom Z-distance such that supports stick well neatly but do not leave blobs on your prints. Typically, the distance is similar to the layer height of your prints, but you can play around with this setting depending on the issues you're experiencing.
Use A Support Interface At Bottom
A support interface will act as a thick layer of filament material between your support structure and the print surface. This interface will make removing the supports easy and act as a good separation between the supports and the prints.
Depending upon your slicer, you can customize your support interface's thickness, area, pattern, and density. Adjust one slicer setting at a time, and don't over-optimize the support interface.
Use Tree Supports
Unlike regular supports, Tree Supports don't contact the prints in several places. These supports form like a tree with a primary trunk and small branches spreading out to support the overhangs. These are visually pleasing and come out in a single piece if you've dialed in your support settings.
The single drawback of tree supports is the time it takes for the slicer to generate these supports. And in many cases, the support branches might not adequately support your overhangs.
Regardless, Tree supports are an excellent alternative to regular supports, and with a bit of fine-tuning, you can achieve great results with these.
Improve Print Geometry
Build Plate Supports and Supports Everywhere are the two primary options in each slicer. Build plate supports use the bed surface as their foundation and does not touch the 3D print. Whereas, with the everywhere support option, the supports will contact your print's surface to hold up the overhangs in your prints.
To avoid lousy surface quality beneath the supports, you'll need to design your models to solely utilize the build plate supports. It will reduce the contact of supports with your print's surface and help you achieve better print quality.