Top 3 Tips For Designer

Avoid Angles that Require Supports

What are supports?

Supports are extra material that act as “scaffolding” that hold up certain parts of a design that angle over 45 degrees. These supports prevent filament from drooping in places where it has nothing to build on. After the print is complete, the supports can be broken off and cleaned up to leave you with your final design. In most cases, the supports are automatically generated by the slicing software that converts your STL file into a format the 3D printer can read, called G-code.

Benefits of Reducing Supports

Although supports are sometimes necessary, there are a lot of benefits to designing in a way that avoids them altogether. Here’s a few reasons why you should care about reducing supports:

Saves time and money: Designs that require a lot of supports waste material, since the supports are removed and likely thrown away once the print is complete. Additionally, adding supports means the product will take longer to print (more material = more time), and we’ve seen supports increase print time by up to 100% in extreme cases. When you add in the time required to clean up the supports post-print, the difference in time to completion can be significant.

Lowers probability of printing errors: Supports add more complexity to the design which raises the probability of errors when printing. It’s common for longer, more complex prints with supports to fail much more frequently than short, simple prints. Keep the design simple to raise the chances for a successful print!

Creates smoother surface finish: Using supports typically creates a rougher surface and again, creates more work during post processing to smooth it out. In some cases, the surface may be damaged beyond reasonable repair when using supports. The picture below is an example of a 3D printed part that is printed with supports (left) and without (right).

If you can’t avoid using supports but do have access to a dual extrusion printer, we recommend using a soluble supporting material like HIPS, or PVA which is discussed in more detail in our filament guide.

How to Reduce Supports

YHT Rule

This is a good way to remember what shapes are safe to design without supports and which to avoid. Thanks to one of our top designers who wrote a more detailed article on Supports and the YHT Rule. The basic rule goes as follows:

a) Anything in a “Y” shape is safe to print without support because it’s a gradual slope which still has enough material beneath it to keep it from drooping. This is another way to think of the 45 Degree Rule, which states that in general, overhangs with a slope greater than 45 degrees will require supports. The more gradual the angle, the better. This is why cone shapes are generally safe.

b) Designs that take the form of an “H”, where the middle overhang connects to either side is called bridging. Typically, bridges shorter than 36 mm long print with drooping of 0-0.5 mm, bridges 36 to 60 mm long print with drooping of 0.5-2 mm, and bridges longer than 60 mm long print with significant drooping of 2-5 mm. These rules aren’t set in stone, however, since it depends on your material and print settings.

c) Anything with a “T” shaped overhang will not have any support and will almost certainly create errors in your print. There just isn’t enough to hold the material up in this configuration.

Split the model into multiple parts

Another way to avoid supports is to split up your model into multiple parts so they can each print flat. After you print the parts, you can bond them with an adhesive like cyanoacrylate (super glue) or a solvent. This can be especially useful for complex designs and larger prints.

Orient your model properly

Sometimes, supports can be reduced simply by rotating your design into the appropriate orientation for printing. For example, in the case of the ‘T’ print above, the need for supports can be completely removed by laying it flat on it’s back. You don’t always need to make changes to your model to improve results.

Anchor your print

Anchor parts of your design that would go beyond 45 degrees and attach them to a different part of the model to avoid overhang. For example, in the first picture below you can see the arms are attached to the back. This is a good method to avoid overhang and allows you to print the design as a whole whereas the model below have their arms straight out which will create some problems when printing.

2) Make Sure your Model is Manifold

Sometimes when you are designing, your model may have some tiny holes in it which, in theory if you filled your model with water would leak. When designing a model, things that appear to be connected are actually not connected or might overlap each other which is a problem when you 3D print them. There are a number of free software on the market that allow you to check and repair your file for errors and holes. Tools like Meshlab, Meshmixer, and Netfabb Basic are all free online software that will either check or repair your files for 3D printing if there are any errors or holes in it.

3) Print it yourself!

Of course, the best way to check if something is 3D printable is to print it yourself. If you aren’t ready to invest in a 3D printer, there are services available that will 3D print your design for you. Companies like Shapeways, i.materialise and Sculpteo will all 3D print a design of your choice. These services have a plethora of different printing materials available from PLA to gold and porcelain. To compare how much it will cost to print your design, All3DP has a printing services comparison engine that will give you price estimates from each company so you can get the best deal.

If your design turns out the way you want, be sure to take a photo of it and use this photo in your design listing. Pinshape conducted a study on the main factors in successfully selling 3D designs and found that designers were 3.1 times more likely to sell their design if they had 3 unique photos of their design from different angles. Why? Makers want to see what your designs looks like once it’s printed, rather than just looking at the CAD file image. We found that those designers who printed their design and posted high quality photos were 7.3 times more likely to have their design sold!

Want to learn more tips? Check out Pinshape’s 3D Printing Design Guide! You won’t want to miss their trick on designing for the right level of detail.