General 3D Printing

What is FDM 3D Printing

Cement FDM 3D Printer

How does it work?

Although 3D printing is a general term and can refer to many different additive fabrication methods, informally 3D printing refers to a Fused Deposition Modeling, or FDM 3D Printing. 

FDM is a method of additive manufacturing where layers of materials are fused together in a pattern to create an object. These layers are fused together, building up throughout the print, and eventually they will form the finished part. 

Plastic FDM 3D Printer

A simple way to explain it...

A much simpler way to think about 3D printers are as fancy computer controlled hot glue guns. Both pieces of equipment have a material that is melted and forced out a hot end.

The 3D Printing Process

Slicer Options

Layer Height

Layer Height is the thickness of each layer used to 3D print a part using FDM. The same object can be printed with different layer thicknesses. 

Layer Height .3mm

Low Detail

Size: 25mm x 25mm x 5mm

83 Layers

6 Minute Print

1 gram of Material

Layer Height .1mm

High Detail

Size: 25mm x 25mm x 5mm

248 Layers

19 Minute Print

1 gram of Material

Infill

Infill or infill density is the amount of material printed on the inside of objects and appears as a honeycomb texture. Infill will support walls and the top surfaces of objects.


 Low infill (10% - 20% is typically used for decorative prints. 


High infill (50% - 80%) is typically used for functional parts that incur stress.

Raft

A raft is a solid plate printed under the object. This setting uses a lot of material and reduces the quality of the bottom surface of the print but ensures a successful print.

Birds Nest

Example of BIRDS NEST. The first print layer did not adhere to the print bed and each following layer did not have a surface to fuse onto.

Peeling

Example of PEELING. The corner of the print did not stick to the print bed and peeled up. Each subsequent layer was squished in that area and deformed the print.

Overhang

Overhangs are the underside areas of a print that will not be supported by material underneath. When overhangs are printed with out supports they can develop defects like whiskers or drooping. The 45 degree rule says that any overhang that is less than 45 degrees should be printed with supports to prevent defects.

Supports

Supports are printed scaffolding to support overhanging areas of a 3D printed part. Supports are designed to be removed but can leave a rough surface where in contact with the part. 

Object Orientation

The rotation of a part before starting a print will affect how many supports will be printed. In the example on the left. The left side would require support material for nearly the entire bottom surface. The right side will require no supports because of its rotation.