3D Printing

In makerspaces today, 3D printers are one of the most common and desirable tools to have, and have a great draw to bring users into a makerspace. The machines are constantly evolving to be more reliable and have more features, plus the costs are much lower than when they first hit the market. A 3D printer creates a physical model from a digital 3D model. General purpose 3D printers come in two technologies: FDM (fused deposition modeling) and SLA (stereolithography).

If you have only occasional need for 3D printing, but can't afford your own machine currently, their are many online providers of 3D printing services- you send them a file, and they send back the finished item in a few days.

FDM Machines

FDM machines have a spool of filament that is fed through a heated extruder head (imagine a precise hot glue gun). Filament is deposited layer by layer to make a part. Fabrication of parts larger than a few inches can take many hours.

SLA Machines

SLA machines draw parts out of a bin of liquid resin. Focused light is used to selectively cure the resin layer by layer as the part comes out of the liquid. Try this article or one of the many other articles and videos available on the web to get more detail on these processes.

Factors to Consider When Selecting a 3D Printer

Cost of Machine
and Material it Uses

Build Plate Size
and Build Volume

Type and Availability
of Filament

Speed and Precision
of Printing

Overall Size and
Portability of Machine

Ease of
Maintenance

There are plenty of reviews and online guides available such as the annual review from Make Magazine, but these typically evaluate the hardware.

Slicer Programs in the 3D Printing Process

For the actual 3D printing process, the maker will also need a "slicer" program. Slicers are the programs that take a solid model (typically an .STL file), and create the tool paths ('G-code') for the printer head to follow in creating each layer of the part. Like the 3D printers themselves, there are many slicer programs and they're evolving quickly, but to help, there are online reviews and guides to assist the user.

The industry standard for 3D models is STL (stereo lithography), which breaks a complex shape into a network of triangles. However, 3D printers typically require a specific file type to generate the required tool paths (G-code) and many have proprietary formats. That means that you can only use the slicer that comes with the printer, which is usually free, and can be very high quality. The takeaway here is that when selecting a 3D printer, be aware that you must choose a 3D printer/slicer combination that works for your user community.

Common Slicing Programs for 3D Printers
Cura Software
Free for Mac/PC

Simplify 3D
$149

Dremel DigiLab
free - specific to Dremel

Dremel Print Cloud
Browser-based

Parts Libraries
Thingiverse
GrabCAD
Sketchup 3D
Warehouse

3D Printing Process and Examples

Filament Types: