News stories about 3D printing feature—the making of custom prosthetic hands or fixing a broken machine by replacing a broken part with a 3D-printed one—make it easy to believe that now, anyone can use a 3D printer. As the cost of 3D printers has dropped over the past few years, buying one for your own projects seems reasonable now.
Students in college and engineering and design programs in universities are often very enthusiastic about using 3D printing. These universities often invest in 3D printers so that their students can learn about this technology.
Three methods are used by the current 3D printers and the cost of the printer is related to the method it uses to create 3D images. SLS (selective laser sintering) and FDM (fused deposition modeling) are used by the most expensive 3D printers. SLA (stereolithography) is the method used in less expensive and most commonly available 3D printers.
3D printers are basically CNC tools that start with the location of a tool in a three-dimensional space, and use an input file that specifies the actions to be taken by the tool. For example, SLA 3D printer files use the file format STL. To print, extruders use the information in an STL file to deposit layers of plastic filaments, epoxy resins, metallic powders and many other materials to create a solid form.
The Computer Center at Hofstra University has been working with 3D printers for several years, and Rose Tirotta, Coordinator of Learning Support for IT Faculty Computing Services, says that in their experience, 3D printers are not well made or reliable. They often break, and at least one out of their five machines is not working at any given time.
Jackson Snelling, an instructional designer at Hofstra University’s IT Faculty Computing Services, notes that there are two problems facing beginners who want to learn to use 3D printing. First, 3D printers are linked to technology, and second, 3D printers are basically a piece of shop equipment. There are a number of YouTube videos that show how to make 3D items, but often a beginner has to have considerable practice with a 3D printer before they are able to use it effectively. In the process of learning 3D printing, it is not unusual to have only one good result out of every five tries.
Beginners who have no engineering or design background can use one of the free software packages, such as Google’s SketchUp, TinkerCAD or AutoDesk 123D, to create 3D models for their projects. The most recent versions of Adobe Photoshop have some built-in 3D features. In addition, there are many sources of 3D images on the Internet, one of the most popular is Thingiverse, and websites that offer images for animated games are also popular resources for 3D printing files.
Beginners are usually advised to start 3D printing by making small objects. Small objects may take about an hour to print, while larger objects often take longer. Inexpensive 3D printers construct objects with layers that are 1-2 millimeter thick, so an object cannot be thinner than this. More expensive 3D printers can print a layer that is only 15 microns thick. It is also important for an object to provide support for parts that are of narrow widths, as thin layers may not be strong enough to support themselves. Although the plastic materials used in 3D printing are not very expensive, it may take several tries to get items that match the user’s expectations.
Some schools do not charge students for 3D printing for class assignments, but many have specific guidelines for the files that they will accept for printing.
The [email protected] website highlights many of the objects that have been submitted for printing to the 3D printer in the school’s Science & Engineering Library, and notes that submitted files are voted by students before they are printed. Printing that will be used for research, teaching, or classwork is favored over items that are for personal use.
Many 3D printing services are available on the Internet and rates are usually based on a charge per square centimeter (cm2).
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