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If you’re an experienced printer, you might already be aware of this: using a 3D printer to create a useful object is not an easy task. There are several limitations that can really stop a project in its tracks. For this reason, the most important method for getting better results is to invest more time into creating a better design.

Creating a design from scratch may be a time-consuming task, but having to redesign an object because it can’t be printed correctly is worse. In order to make it easier for designers to create printable objects, a conceptual framework called “design for printability” (DFP) was created. The framework helps deliver better design ideas and models. [no_toc]

Fused Deposition Modelling

As of right now, fused deposition modelling, also known as FDM, is the most widely used form of 3D printing. Printers using this model create objects by stacking layers of plastic (PLA, Nylon, etc.) on top of each other. The printer’s heated nozzle deposits each layer into thin strips. The printer head that’s housing the nozzle must be powered by at least 4 motors. Each additional motor can deliver an extra level of speed and precision.

When it comes to creating a new 3D object, there are 4 designs that can help you achieve your goal. Understanding their geometry and possible applications is the first step to creating better designs for your project.

Single Extrusion Designs

By far the easiest design a 3D printer can create is the single direction extruded shape. These are the basic designs that allow the printer’s nozzle to follow a direct path. The best results based on this design are obtained when the largest face of the object is the one laying on the printing bed. Single extrusion designs offer better bed adhesion and surface finish. Moreover, there will be less warping and skewing thanks to the improve stability of the object during printing.

Multifaceted Designs

Obviously the previously mentioned designs are also multifaceted designs, but this section refers strictly to objects that have angled faces. These designs are more complicated to print due to their decreased stability. Moreover, some designs require the object to have overhang areas that the printer might find difficult to print. However, there is a workaround for this problem: splitting the design into multiple parts. It’s not an ideal solution, but as long as the final result does its job satisfactory, there’s no reason to stress the printer by creating a design that’s too complicated for it to print out.

Amorphous Designs

By far the trickiest 3D design, an amorphous object lacks stability entirely, especially if it doesn’t have at least one flat surface. Similar to multifaceted designs, amorphous designs can also benefit from slicing. Assessing the topological information of the initial design can offer enough information to know where the slicing would offer the best stability. For increased stability and bed adhesion, opt for a slicing that offers the largest flat area.

Modular Designs

For more advanced modellers, modular designs become not only an option, but a solution to most creations. Instead of having to glue pieces together as with slicing, modular designs use custom joints to connect the modules together. They’re more complicated to create, as the joints must connect flawlessly, but once you’re comfortable with the previous designs, trying out modular designs won’t seem as complicated.