When designing a product that is 3D printable one of the most important parts is deciding what material you are going to use. This affects your cost, print settings, and design constraints because there is a wide variety of materials, with an even wider spread of price points, and they all act a little differently when printing.
Starting with, in my opinion, the most important is material properties. This should be the first thing you ask yourself. In the core operation of this part, can this material handle the use case? For example one of the most popular filaments used in FDM printing is PLA, PLA does not handle UV exposure well, and softens at relatively low temperatures, making it not the normal go-to for designs that are going to live outside. PLA is quite strong though when printed correctly, does not deflect much as it is loaded, and is very cost-effective making it a perfect plastic to use for pieces that will be used indoors or need to be rigid in use.
Once you know the material can be used for what you need. It is important to make sure your print settings and design highlight the strengths of the material and not diminish them. This means making sure your layers are aligned with your load for functional parts. Also don’t have bridges too long for the material to be able to span and for extra stretch filaments like TPUs and PETG try to reduce the chances for stringing by not having too many individual bodies per layer when printing, sometimes this can be fixed by just how you orient the part on the print bed and won’t even need a design change.
Choosing a material is an important step in designing your product, but once you find the correct one it can make a world of difference and even allow you to create products that wouldn’t be possible in any way besides 3D printing. It can be tricky sometimes so don’t be afraid to experiment. One of the biggest upsides of additive manufacturing is to switch between materials or make a design change you lose a few minutes re-slicing the model and a few more switching out spools but for almost no cost you have an even better product ready to go. If you have any questions please don’t hesitate to comment below or email me at email@example.com and I will help as much as I can.