Choosing the Right 3D Printer

New technologies can be intimidating. I’m sure some of you remember a day when being online was for hobbyists and only the most hardcore techies had an email address. Fast-forward to today and most of us would have a hard time naming someone who isn’t online at least part of the day. The speed at which new technology changes how we interact with the world has never been greater, as is the need to keep up with such tech so as to not fall behind.

One of these new technologies is 3D printing. “New” is a bit of a misnomer, as additive manufacturing has been around since the 80s, but its proliferation into mainstream society has been recent. Accompanying the growth of the printing industry is a growth in the types of 3D printers. Fused-deposition modelling, stereo-lithography, and selective laser sintering are three of the most popular kinds of printers, and the three we will discuss today. Each of these technologies have their own unique qualities that may or may not be ideal for your purpose.

Choosing the correct printer for your application is the first and most important step toward incorporating this technology into your life. The two questions you must first ask yourself are “How much am I willing to spend?” and “What style printer meets my needs?”

Price Point

Establishing a price point for your printer should be one of the first things you do. 3D printers run from $100 to over $500,000. Most printers under $1000 are more novelty items than a machine that can provide manufacturing solutions. Some of these can be useful as an introduction to the tech, but for professional use, I recommend a rule of thumb of only looking at printers above $1000.

Printers in the four-figure range will offer great rapid-prototyping capabilities and some can even deliver high quality parts, but you will sacrifice speed and build size compared to the higher-dollar printers. The printers in the $10,000 and above range offer speed and size unmatched by anything else on the market. They can even produce end-use parts, if that is your goal.

If you are new to the concept of 3D printing and want to experiment around or if you are looking to prototype an idea prior to production, expect to pay $1000-3000 for an appropriate printer. If you are more interested in making sellable parts without too much post-processing, printers $3000 and above will be the place to start.

Style of Printer

Fused-Deposition Modeling (FDM)

FDM printers are some of the most common printers on the market. They are a simple point of entry from an ease-of-use standpoint and they usually occupy the lower range of prices. FDM printers operate by feeding a thermoplastic filament through a heated tip, melting it, and layering molten plastic onto a build plate. These printers can produce robust parts at a reasonable speed, but due to the mechanical constraints, the parts will have visible layer lines and a rough surface resolution. As such, FDM machines can be great at prototyping but struggle to deliver end-use products.

We at Sondare use a Lulzbot Taz 6 for our product prototyping. This model is reliable and has a large (1 ft3) build volume. When modeling our mobile cases and acoustic devices, the Taz 6 allows us to prototype each revision the day that the change is made. Having a model in your hand is invaluable to product development. The difference between holding a model and looking at one on the computer has helped us move along in the evolution of our products by allowing daily testing. It is also of great use to a multidisciplinary team, one that may have members unfamiliar with CAD modeling.

Stereolithography (SLA)

SLA printers generally make nicer parts than FDM printers. These printers produce parts by curing them from a photo-sensitive resin, one layer at a time. Since the material is chemically cured rather than melted and hardened, parts made from an SLA printer have higher surface resolution and greater isotropic strength than those made from an FDM machine. SLA printers also use thermoset materials, which offer greater strength, while FDM printers use thermoplastics.

SLA printers do have their drawbacks, however. They often have a higher initial cost, with most SLA printers being over the $3000 mark. The resin is also substantially more expensive than FDM filaments. A one-kilogram roll of PLA for an FDM printer might cost around $25, but even the cheapest resins are no less than $80 per liter (roughly one kg). Depending on the product you are prototyping, this cost should be considered, especially if you are early in the product ideation process. Finally, SLA printers require more maintenance than FDM machines. The resin vat and fluid lines require more attention than the nozzle of an FDM machine.

Selective Laser Sintering (SLS)

SLS printers are a bit of a different animal than the previous two types of printer discussed. The SLS process is like SLA, in that an SLS printer uses a vat of material and a light source, but rather than resin, the material is a powder, and the light source is a laser, not UV. Since the material being sintered is a powder, some SLS machines can handle metal in addition to plastics. Metal-capable SLS printers excel at making complex metal parts and jewelry. Plastic parts made in this method will often be some of the strongest 3D printed parts.

Another benefit of SLS printers is that they do not require support structure underneath any overhangs in the part. This helps save material and can create highly complex parts. One advantage that this creates is that parts can be printed on top of one another. That is, once one part is finished, powder gets pushed over the top and another can be made above the previous part. This maximizes the utility of a large build plate.

With all these advantages comes one main drawback: price. SLS printers are the most expensive of the bunch. The highest price point brings the highest bar of entry, but if you can make the math work within your margins, SLS printers will make the highest quality parts.

With this introductory guide, you should now have a good idea of what to look for when shopping for 3D printers. Whether you are just starting with a new product idea or you want to move into self-manufacturing, there is a printer for your needs. Stay tuned for more 3D printing and product design tips!