3D printing: A materials games

3D printing is all about what will work best for the part

By Fred Kaplan

Matterhacker’s lab where products are tested and used

The first 3D printer company I worked for sold printers that made objects out of a refined and expensive form of gypsum. Gypsum has been called “Plaster of Paris” due to the proximity of the Montmartre quarries to the City of Lights. Gypsum is also the main ingredient of sheetrock or drywall — not exactly the strongest or sexist material that one would expect from a 3D printer but it worked well for its purpose at the time.

From humble plaster beginnings, 3D printing has always been a materials game. One cannot say what material is the best because every printing need is different. For many, PLA is the best material because it is easy and inexpensive. For the aerospace community, Ultem /PEI or PEEK are considered the holy grail of 3D-printable materials.

SPOILER ALERT // There will be a rash of new desktop metal printers coming out in the next twelve months which will produce fully dense metal part on what is comparably inexpensive $120,000 printers. //

The best materials are subject to what your intended use is for your 3D-printed part. Which can be divided into three groups.

• Rapid Prototype: a geometric representation of the object to be viewed, held or snap fit to test the shape of the object perhaps in relationship to another object
• Functional Prototype: The printed part may be subject to heat or stress to determine if the geometry fits and functions under specific conditions I would put 3D printed part that will be a casting in this category.
• End Use Pars: which includes Tooling, Aerospace, Automotive, Medical, Dental, Jewelry, Food, Bioprinting, Clothing and more

Given the wide variety of uses for 3D-printed objects — everything from toothbrush holders to a functioning kidney — it’s crucial to know what materials you want before you purchase a 3D printer because the material you print with will affect the geometry of the part.

We spoke to MatterHackers’ Director of Marketing Dave Gaylord to get a greater understanding what 3D-printable materials are being used and why would one choose any particular material. Granted, we could have taken a six-year degree program in chemistry to get our answer but we figured asking Dave was like the same thing. MatterHackers opened in 2012 and currently represents over 70 manufacturers of 3D printers as well as a large assortment of filament materials including PLA, ABS, nylon, NylonX, SLA resins, Flex, PETG and more.

“sets MatterHackers apart is that they test and use the products they sell, much the way you would expect an innovative lab to work. Matterhackers’ website provides sought-after user forums where customer’s questions are answered by MatterHackers’ trained staff.

3D Printr Magazine: Can you tell me about MatterHackers?

Dave Gaylord: “MatterHackers is the largest 3D printer retailer in the United States. We are known for our customer service and we feel confident in our ability to provide all the information our customers need in order to use their 3D printer successfully. Our website features how-to guides on many subjects including how to calibrate your extrude, use cases that illustrate 3D printing applications, and generally inspire our customers with interesting designs. We write features stories about new products and accessories. There are 3D printer reviews and it’s a go-to resource for 3D printing. Recently we have been adding video content.”

3D Printr Magazine: Tell me about Matterhackers’ customers.

Dave Gaylord: “We have three distinct types of customers:

• Hobbyist and Do It Yourself customers who are the root of the open source movement and our primary customer
• The education community.
• Professional Engineers. We have been selling into the professional market such as engineers what makes these customers unique they require greater geometric tolerances and the absolute best user experience. These customers will use 3D printed parts as an end use part.”

3D Printr Magazine: What materials are being used?

Dave Gaylord:“PLA is the most popular material, it’s easy to use so everybody uses it — unless there is some specific case requiring a more robust material. PETG (Polyethylene Terephthalate) is going to overtake a good bit of the market in the next year or two. PETG is easy to print with and it’s more durable. Our more advanced users are printing in nylon. MatterHackers’ in-house engineers are using nylon almost exclusively. It’s a stellar material that makes really strong parts and the layer adhesion of nylon is remarkable. Last year we announced our NylonX material which is a chopped carbon filled nylon. It’s a super strong, super stiff material that looks great right off the print bed. About a month ago we launched a PRO Series nylon that offers seven different color materials. Prior to this nylon was only available in the natural off-white color.”

3D Printr Magazine: What do you think is the best support structure method?

(3D printers add what’s called “support structure: when printing overhangs and to void the problems when the geometry would have plastic printing in mid-air. The most common form of support structure is a lattice of the printing material that is broken away in a post-printing process.)

Dave Gaylord: “Well that depends. If you don’t have dual-extrusion, the only option is printing in one material and breaking away the support material. If your 3D printer has dual-extrusion — meaning that the printer can print two different material in the same build — an additional material can be printed to physically support the build material. There are two soluble support materials — PVA (Polyvinyl alcohol) which dissolves in water when used with PLA plastic — and HIPS (high impact polystyrene), used with ABS plastic and removed using D-Limonene which is derived from citrus oils. We find that same material break-away supports work just fine. MatterHackers’ slicing software MatterControl has really great features that make easy-to-remove break-away support.”

3D Printr Magazine: Can you tell me more about the MatterControl software?

Dave Gaylord: “MatterControl software is free open source software that organizes and manages your 3D prints. It’s designed to help you get the most out of your 3D printer and its available for all operating systems including MatterControl Touch which is an Android-powered touchscreen controller that turns your 3D printer into an independent internet-connected device. Matter Control ships with many 3D printers as the original slicing software including SeeMeCNC and Robo3D. The slicing engine is continually being updated by our in-house software engineers. How can you beat free software that is easy to use?”

3D Printr Magazine: What’s your dream 3D printable material?

Dave Gaylord: “The material chemists in the 3D printing space have been very busy. New 3D printer materials are constantly being developed. We find the problem with many materials is that they are cost prohibitive for our market. PETG checks off a lot of the boxes on my checklist, particularly ease of use, strength, and durability. PETG is used to make water bottles, food packaging, and countless other plastic items. It combines the durability of ABS plastic with ease of use of PLA. Anything that PETG lacks as a 3D printable material, nylon fills the gap. It’s our primary material at MatterHackers.

“Nylon filament is incredibly strong, durable, and versatile. It warps a little if you don’t handle it properly and it is perceived to be a hard material to print but if you know how to handle it — it is an amazing tool. It is flexible when printed thin with very nice inter-layer adhesion. It’s low friction coefficient and high melting temperature makes nylon an excellent choice for 3D printing gears. Printing nylon requires temperatures higher than 240 degrees C. Most 3D printers come standard with hot ends made of PEEK and PTFE which begin to breakdown above 240 C, burn and emit noxious fumes. Make sure you check with your 3D printer manufacturer or email us your 3D printer information if you are unsure if you can print nylon safely.

“Most 3D printers can be upgraded with metal hot ends to print nylon safely and successfully. Nylon is also hydroscopic which means that it can absorb 10% of its weight in 24 hours so it is best if the Nylon material is dried in an oven at a temperature of 160-180 F for 6-8 hours. Store nylon in an airtight container.

“You can prevent the Nylon from warping by printing on a glass bed. We suggest a bed heated to 75 C with a thin layer of glue. To sum up, nylon is a great material that some people perceive to be difficult to print but if you use the tips I just mentioned or look at the information on the MatterHackers website you will enjoy the superior material characteristics of nylon. So I guess my dream material is either nylon or PETG.”

3D Printr Magazine: What’s MatterHackers bestselling material?

Dave Gaylord: “Our Pro series materials are our best sellers. The Pro Series filaments are engineered to highlight the strength of each type of material. Made to the highest tolerances in the USA. The PRO series includes PLA, ABS, PETG, nylon and Flex. MatterHackers stick behind the Pro series material like all the rest of the products we sell but you can use the pro materials with full confidence that you are getting the finest 3D printer material.”

3D Printr Magazine: Does MatterHackers sell material to print metal?

Dave Gaylord: “We sell thermoplastics filament infused with metal powders. The finish looks like bronze or stainless steel when you sand and polish it. They are not as strong as a fully dense metal part but it doesn’t require a $100,000 printer and a Hazmat suit.”

3D Printr Magazine: How have the 3D printer manufacturers improved their printers?

Dave Gaylord: “3D printer manufacturers have really dialed in user experience to the point that you can be 3D printing five minutes after the box is opened. Matter Controls is focusing on improving the user experience by creating presets to get the user printing quickly and having those settings match the different materials.”

3D Printr Magazine: How can you sell 70 printers? Does that confusion people?

Dave Gaylord: “It’s awesome! We have great conversations with our customers. We ask about their expectations and what their needs are. We ask questions such as, ‘Do you need a large build volume?’ ‘Are you focused on print speed?’ ‘Do you care about the visual aspect of what the printed part looks like?’ ‘How many printers do you want — one or a fleet?’ We can really dial in the needs of the customer because we have so many options, and each printer we sell is extensively tested by our team. We know the printers intimately and we can make strong recommendations based on our personal experiences.

“Having a great experience with a 3D printer really comes down to making sure that you — as the 3D printer user — understand what you need and what you can expect from the printer you buy. This is where MatterHackers excels. We regularly send out informative emails. Each printer we sell excels in different areas so it is important to make sure the customer gets all the information about the printers or the materials. People trust us because we aren’t a printer manufacturer. We have a broader vision of the whole 3D printing landscape.”

Fred Kaplan is a 3D-printing material specialist, who has worked with SLA, SLS, FDM, ColorJet, ADAM, DLP, LOM, FFF, MultiJet, Polyjet, and SDL 3D printers. Specializing in matching the best technology to a particular 3D printing application, he has also worked with many brands of 3D scanners and many CAD packages.

Prior to his work in additive manufacturing, Fred received a Los Angeles area Emmy and other awards for documentary filmmaking.