Good practices for CAD design and 3D printing
This page is dedicated to collect good practices and examples of things to avoid when you design parts for manufacturing and especially 3D printing. This is not intended as a complete guide on how to do these things.
CAD design
3D printing
3D printing or not?
First of all, not everything is good for 3D printing. You should think about the usage of your part, the constraints, the shape, etc. and make a conscious decision whether it makes sense to 3D print it or not.
Flat part with just some cuts or holes? → Rather laser cut
Cylindrical part? → Buy a tube
Big box? → Think about building it from wood planks or metal sheets for the sides, eventually connected together by small 3D printed parts if necessary.
Diverse
Avoid sharp edges! When an outside edge is smaller than 90°, think about creating chamfers or rounded edges. Your fingers will thank you and the part will be better printed.
Avoid thin and long components. These will either break if printed vertically or might deform and bend.
Think about the orientation in which your part will be printed. Ideally, avoid overhangs. If not possible, keep in mind that some support will be necessary, which will make the area where there was support not smooth.
Always keep in mind that the 3D printer does not have an exact precision and think about tolerances. For example, if you want a pin to slide into a hole, they should not have the same diameter!
Consider dividing your parts in subparts to optimize the printing.
The support added to the bottom here adds almost 20% of printing time (6h47 → 8h03) and almost 30% (98 g → 127 g) of material!
In this example, the parts in blue force the use of support on the complete surface of this big part. This represents a big loss of printing time and material and will make the surface not smooth. One possibility would be to print these parts separately and to fix them together after.