3D Printer Buyer’s Guide

3D printers are becoming more available and affordable. Interested in purchasing one for the classroom? Below are some helpful buying tips and a rundown of available models.

What to Look For

• Some 3D printing projects take hours, so it’s crucial to look at the print speed of the machine you plan on purchasing. Different building materials can affect speed, and complex models with lots of edges can result in slow prints. If you want quick results, look for a top speed of at least 20 millimeters per second.
   
• Most printers come fully assembled, but others are sold as kits that need assembling. Although some machines have a lot of parts, educators with basic mechanical knowledge can easily put them together.
   
• Most models have single extruders for the filaments, which are the plastic pieces used to create the products. Models with single extruders can only print one material or one color at a time.
   
• Consider filament width when purchasing a printer. Most 3D printers use plastic filaments, which are 2.2-lb. rolls that cost $40 to $60 per roll. There are two widths available when purchasing your printer: 1.75 millimeters and 3 millimeters. Most printers use the 1.75-mm type.
   
• Build areas are measured in XYZ dimensions. Cheaper models have smaller build areas. For a decent-sized product, look for a build area of at least 5 x 5 x 5 inches and 13 x 13 x 13 cm.
   
• The resolutions of 3D printers can be measured in two ways: horizontal (XY) or vertical (Z). Horizontal resolutions are the smaller movements in 3D printing. The smaller the resolution, the finer the detail. Look for a measurement of 0.01 inches for fine, horizontal resolutions. Vertical resolutions are the minimum of thickness: the larger the number, the thicker the product. Most printers work with a layer thickness of 0.2 or 0.3 millimeters. Some printers allow users to adjust layer thickness.
   

Models

Entry-Level Filament 3D Printers: Solidoodle or Cubify Cube

Price:  $300 to $2,000

Description:  These printers use a filament disposition process whereby the plastic is processed, melted and then distributed in layers to create the final product. The machines work with two types of plastic: ABS (which is used in Legos) or PLA, an organic version. The printers have a single nozzle for the filament and use 1.75-mm or 3-mm filaments, so users can choose from a wide range of colors. Most machines with basic software. For those that don’t, users can access a variety of software options.

Pros:  These types of 3D printers are relatively cheap and easy to set up.

Cons:  The printers have a single extruder, which means it can only print out one material or color at a time. The build area is also small: 4 x 4 x 4 inches (10 x 10 x 10 cm).

High-End Filament Printers: MakerBot Replicator 2 or RepRap Mendel

Price:  $1,000 to $3,000

Description:  Models such as the MakerBot Replicator 2 or the RepRap Mendel offer more sophisticated FDM filament features, such as multiple extruders, improved vertical resolution and thinner layers for smoother prints.

Pros:  The larger build area (often up to about 10 x 6 x 6 inches or 25 x 15 x 15 cm) enables bigger prints. The multiple extruders also allow for more materials and colors.

Cons:  These printers are more expensive, and the sophisticated parts could break with heavy use.

Other-Material FDM 3D Printers: Hyrel

Price:  $2,000 and up

Description:  These machines use air-dried materials other than plastic, including clay, Plasticine and Sugru. Plasticine can create more flexible models, and with its ability to bend like rubber, Sugru is ideal for elastic products.

Pros:  The printer can support a number of extruders and use materials that aid in the printing of pots and dishes.

Cons:  This machine’s support for material is experimental, meaning that the user will have to figure out what it can and can’t use.
 

Stereolithography (SLA) 3D Printers: Form 1 or the B9Creator

Price:  $3,000 and up

Description:  These machines use a photosensitive resin and a digital projector or laser. The light shines on the material, causing it to solidify.

Pros:  The printers offer very high resolution—smooth prints with .012 inches of horizontal resolution and .001 inches of vertical resolution. The printing process is also quicker than with FDM filament models.

Cons:  Only a limited range of fairly expensive resin colors is available. For the Form 1, the resin costs $149 per liter and is available in gray or clear. The build area is also on the smaller side: 6 x 5 x 5 inches (15 x 13 x 13 cm).

Powder 3D Printers: Zprinter 150

Price:  $10,000 and up

Description:  In powder printing, a fine powder is spread over the print surface. Then a laser melts the powder, or a solvent liquifies it, forming the layer. Powder printing can handle materials including metal, glass and plastic.

Pros:  The machine can make products in multiple, customized colors; some models can print from powdered metals.

Cons:  These printers are more complex to assemble, and the solvents and laser components are expensive. Only open-source designs are available, which owners can try to build themselves.

Related resource

Tech in the Classroom: 3D Printers

Article by Kassondra Granata, EducationWorld
Education World®             
Copyright © 2014 Education World