KENNETH R. ROSEN
WHAT I INTENDED to do with my 3D printer, I can’t remember. I vaguely remember wanting to print big things, but I was unsure what those might be. More abstractly, I was hoping the printer might combine several hobbies and interests into one: computer programming, additive and subtractive manufacturing, computer-aided design, tinkering, and an unyielding desire to create something, anything.
Expecting too much of my printer was my first mistake. I stumbled into dozens of other pitfalls after the printer arrived, up until the day I placed it on a shelf in my garage and solemnly declared across my family’s breakfast table that I was done (for now) with the 3D printer. The room virtually erupted in applause.
That’s because my hobby became an obsession, something I could have avoided had I understood the limitations of both my skill set and the capabilities of the printer. Meanwhile, since March 2020, additive manufacturing has been one of the few industries to grow despite the pandemic. The machines have proven their commercial mettle during disrupted supply chains and has offered rapid prototyping capabilities to at-home renaissance workers looking to aid the health care industry.
And with 3D printers (some available to consumers, others intended for industrial operations) now creating everything from concrete homes to organic biotech material, their popularity is unslowing.
Here are a few tips before starting your own foray into 3D printing.
Know Why You’re Buying
3D printers range in size, price, precision—and, because of those variables, cost. Do you plan to print toys for your children, or is it a way to introduce your kids to STEM? Do you have small do-it-yourself projects around the home for which 3D-printed parts could save you money? Or are you simply looking for a desktop hobby that'll let you print doodads and bric-a-brac like a toothpaste tube squeezer or bookshelf bracket?
Low-cost, desktop printers range from $100 to $400, with more accurate and larger printers costing north of $1,000. Professional and enthusiast printers—some of which can print ceramics, metals, sand, and other materials beyond plastics—can cost up to $10,000. Anything beyond that would be considered industrial and could easily cost up to $250,000.
For the purposes of this guide, I’m assuming you’re looking for desktop consumer printers. With the recent explosion in the availability of printers, anything less than $500 is sufficient for household jobs. This range will all meet similar standards of accuracy and speed, and maintain options to upgrade.
Choosing a Type of Printer
3D printers have existed since 1983. The one method of 3D printing back then has today become nine different types of printers. For the first-time buyer, however, fused deposition modeling (FDM) and stereolithography (SLA) are the easiest to learn and require the least know-how to get started.
FDM works like this: Thermoplastics (are forced through a nozzle heated to over 200 degrees. The plastics, known as filaments, come in a variety of types: polylactic acid (PLA), polyamide (PA), acrylonitrile butadiene styrene (ABS), polyethylene terephthalate glycol (PETG), or some with wood and carbon laced into the plastic. The most common nozzles are .4 mm in diameter (the smaller they are, the higher the resolution), and they hover over a build plate or heated platform at about the thickness of a Post-it Note. The build plate, sometimes also heated, helps the plastic stick and cool down as layers accumulate and harden. The nozzle moves on tracks or gantries (some have two axes, some more), assisted sometimes by actuators, servo motors, rack-and-pinion structures, or slide guides. The final print usually needs to be cleaned of excess plastic with a hobby knife or wire brush, but this isn't always necessary.
SLA is a process that boosts accuracy and precision while lowering production time and post-processing, or cleaning, of the printed object. To start, a chamber of liquid photopolymer plastic is heated, and a build plate rises from the plastic as an ultraviolet laser scans mirrors to produce each thin layer. A thin blade moves across each layer to ensure a clean and thin layer of resin is placed onto the build surface which, unlike FDM, moves upward rather than downward, building from the top down. Automotive, medical, and aerospace industries favor this type of printing for its stronger, more accurate renderings. The post-processing is also much simpler: Dip the 3D part into a bath of chemicals to remove any excess resin.
Beyond the choice of printing process, your selection should then focus on one or two areas of compatibility to align with your needs and expectations. For example, you might want a printer that has a larger print area to make larger objects like functional cosplay parts, or a smaller print-area for making toys and tools. You might also consider what speeds and resolution the printer is capable of, but for the first-time buyer the standard speed of 100 milliliters per minute and between 10 to 200 microns of resolution will get most jobs done.
My advice is to pick something that fits on your desk and has a small build plate. The bells and whistles can come later. I wasted too much time worrying about speed and accuracy when I first set out to buy a printer, things that can always be improved upon later and something that is generally part of the regular calibration before every print. Most printers come ready to print right out of the box, without having to order additional materials, build plates, or wash kits.
Whichever printer you pick, the process for making a print is virtually the same. You model a design through computer-aided design (CAD) software like Autocad’s Fusion 360 or Tinkercad or download the file off one of the many 3D file forums, like Thingiverse or YouMagine. You send that file to a program known as a “slicer,” which automates the process of turning that CAD file into something the printer can render into an object. Once you’ve uploaded the file to the 3D printer, it builds the object in layers using the “slices” from your program of choice.
Beware the Upgrade Spiral
I was far from modest at the start. I chose a printer with a large, heated build plate and bought several spools of extra filament, believing I’d be running the machine at all hours for days on end, printing everything from bookends to desk organizers. I was extremely misguided. And when those expectations weren’t met, because the printer is something that requires attention, calibration, and patience, I looked for upgrades and tools to improve print quality and lower print time. (Sometimes objects can take hours or even days to print, depending on their size and density.) This led me to purchase servo motors and microprocessors I did not need, and which only served to complicate my efforts. It also stripped all the fun out of the hobby.
There are, however, three upgrades I’d recommend for any printer if you’re keen to upgrade before you begin and are into disassembling and reassembling your tools.
Nozzle: Upgrading the standard brass nozzle to hardened steel can increase the lifespan of your nozzle and will immediately improve your print quality, and a range of different bore diameters supporting the standard 1.75-mm filament diameter will also offer greater flexibility when printing.
Filament: Most printers will ship with a spool of filament to allow you to get started. But it’s only enough to print a few calibration tests. You’ll want to spend a bit more on good filament, anywhere from $30 to $50 a spool. Lower-quality filament will only lead to frustration where there needn’t be.
Rubber feet or concrete pavers: Consider this a pro tip. Using rubber feet, like those found on washing machines, or a set of brick pavers as the base for your machine will dampen vibrations and settle your machine as it moves about the build surface. The benefits for such a minuscule upgrade are seen immediately.
Don’t Set and Forget
You can purchase a Raspberry Pi, install a Linux-based operating system called Octopi on it, and monitor your 3D printer and its progress from your smartphone wherever you have internet connectivity.
In the beginning this will be tempting. Don't do it. Instead, stick with the printer and watch to make sure prints don’t go awry, as they surely will: A nozzle will knock a layer off and spin itself into a bird's nest of hardened filament, or on the last three layers a curled edge on the base of the model will loosen and dislodge the entire print, destroying 17 hours of slow progress toward completion. These are things that can be stopped before they get worse.
Take those first prints for what they are: learning experiences. With practice will eventually come mastery, at which point the upgrades and bells and whistles will make more sense and bring you greater satisfaction and reward. Learn the fundamentals—what speeds your printer and filament extruder enjoy, what types of plastics work best at your elevation and ambient temperature, and where you can improve on your creation and modeling inside the CAD software—before jumping ahead.
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