From the course: Design for Additive Manufacturing: FDM

The body of a 3D print - Fusion 360 Tutorial

From the course: Design for Additive Manufacturing: FDM

Start my 1-month free trial

The body of a 3D print

“

- [Instructor] Let's take some time to identify components in the body of a 3D print. We're going to talk about this while bumping through a visualization. So we've already talked about the different ways to start a print, a brim printing directly to the print plate, et cetera, or in this case using a raft. Bump through those raft layers to the first layer of our print. Now this is called a floor or a bottom layer. These layers are made up of one or more outlines called a wall, shell, or perimeter and then the outline contains a solid fill. There are usually three or more floor or bottom layers and the fill direction alternates on each layer. You have control over the wall thickness either by controlling the dimension or the number of outlines and you can also control the number of floor and bottom layers as well as the pattern of the solid fill so you have a lot of options there. Now next comes the body of the print. There's an outline composed of one or more lines, but instead of being solid like a floor or a bottom layer, the infill is printed in a lattice structure. You can control the number of outlines creating the wall or shell of your print as well as the density and the pattern of the infill. The print finishes with roof or top layers which are similar to the floor or bottom layers, a number of outlines with a solid fill. Now most slicer software will have good default values for all of these things, top, bottom, infill layers, but there are some examples where you might want to alter these values. Now it's worth noting that this print is very similar. Layers are either top bottom layers or they're infill layers, but an individual layer can actually have elements of both depending on the geometry of the print. Let's go further in depth on infill. Infill percentages between five to 50% are common. To increase the strength of a print, increase the infill density. You might also consider adding more shells or additional top or bottom layers. Want to save time? Reduce infill percentage or the number of shells. Now some slicers have smart infill options that place infill only where required to build the upper layers so this isn't a good choice for parts that require uniform strength, but you can cut out a lot of print time from visual prototypes or decorative prints. You also have control over the type of fill on solid top and bottom layers. For certain types of prints, changing the fill pattern on solid layers can subtlety change the appearance like this topographical map. There's a subtle but important difference between the line and concentric fill styles. Or try this, instead of printing this file with the default setting as shown on the left, it can be printed as a hollow vase by turning off infill, the top layers, and adding more shells. It's a great example of how cam choices can significantly alter the CAD design.

Contents