Getting On the Move with a 3D Printer

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The previous article, “3D PRINTING: WHAT IS IT ACTUALLY GOOD FOR?” advised you about how to enable 3D printing to start projects and businesses. This next article is about choosing a 3D printer and getting it up and running. There are now hundreds of brands on the market, quality varies dramatically and installations are not a simple matter of plug-n-play. There are only a few printer brands that have the right experience, customer-oriented approach and know-how to get the fundamentals of the machine in order. So with the guidelines in this article I am pleased to inform you, 3D printing enthusiasts and professionals, about purchasing a new 3D printer for use at home and non-industrial workplaces like offices, studios and schools.

We are only treating FFF (Fused Filament Fabrication) printers here, for the following reasons:

  • Some SLA printers are affordable but while they have great accuracy, the shelf life of materials is limited, materials are up to four times more expensive per unit of volume, materials are toxic and/or irritant to the human body. Also these printers use resins that are not suitable for testing mechanical properties often desired in end-use products. These are mostly used for showcase and mother models for secondary processes such as molding or casting.
  • SLS printers are still too expensive with small build volumes, and require an industrial environment.
  • FDM systems such as Stratasys Dimension are in the lower range of professional printers but too large for in the house, with materials being up to six times more expensive.
  • FFF systems are the only ones with a lot of materials available, a lot of them moreover are open-source with a large community base.

The following factors are most important when considering a 3D printer today:

  1. Dimensional Accuracy. Cartesian printers are generally more accurate than the Delta, Scara and Polar systems. A Cartesian 3D printer separates movements of the X, Y and Z dimension so its position can always be controlled. It does so by having three linear rods bearing the print head. A Delta printer nears the target position through three rods that triangulate each coordinate. A Scara printer is a robotic arm that handles movements in the XY plane, and a Polar printer has a rotating XY printbed with the nozzle moving only upwards. High accuracy is paramount because with vibrations above a certain level this will become visible in the print as a Zebra effect. You can somewhat programmatically control this with firmware settings such as XY-jerk and maximum acceleration. Also the belts of the 3D printer are important and while most are good quality, GT2 belts for example are better than standard ones. Make sure the belts are so tight you can stretch them less than one centimeter up or down. You can buy simple torsion springs to adjust belt tension. Some 3D printers have a moving printhead with integrated direct drive filament feeding system, that can influence print quality because of its inertia.
  2. Electronics quality. Controller boards often fail and the best ones come from Europe and the US and are brand-specific. If you have a generic non-EU or non-US board, it is much more likely to fail. Pay attention to the boards having a variable resistor for adjusting the voltage going to the motors.
  3. Steady extrusion. If your printer does not have a reliable extruder, it will require a lot of maintenance. Some extruders leak if not assembled perfectly, some work only for one type of material, others simply do not transfer enough force onto the filament or have too much cumulative friction along the feeder system. While some companies manage to have a well working Bowden tube system, I recommend a direct drive system, especially if you are working with flexible materials.
  4. Multiple extruders. The ability to print with multiple materials is a desirable capacity both for hobbyists, artists and professionals. The thing with multiple FFF extruders though, is that while one extruder is printing, the other one will have some material still running out and still being in contact with the print. That makes a dual extrusion print of less quality than a single extrusion print. Some printers have solved this using a single nozzle and exchange system. This solution requires an exchange tower where the mixed filament gets deposited before starting with clean material on the print. The thing is that, before the nozzle would be completely clean it would require quite a bit of wasted material slowing down the print. Also, filaments have a sweet spot when it comes to temperature so this can only be used on filaments of the same brand. Keep in mind that while most 3D printers use 1.75mm filament, other use the 2.85 or 3.00 mm filament standards. To gain a quick level of expertise I recommend to stay with one brand and choose for one standard to maintain a single inventory.
  5. Build quality. Like a human body, a 3D printer is a quite complex machine with several sub-assemblies coordinated together. A build can appear healthy, but if there are issues underneath the skin these can manifest rapidly or slowly over time. In order to keep it healthy, you need to preventively maintain it by lubricating the rods and axes as well as the Bowden tube, keep the print bed calibrated and as clean as you can, maintain the PCB heat sinks and wires, tighten all belts and screws, and remove rests of filament in the area. Also keep filament dust and moisture free and stored dry. If you buy a printer, check all components for long-term stability. The best printers will make for a good working life of five years or 5,000 running hours. Plastic components, except for acrylic, will slowly disintegrate and as with wood, start bending and distorting. Composite and steel components will be very stable over time so they are worth investing in. Next to a 3D printer you will need basic tools: a pair of tweezers, allen keys, screw drivers, sewing machine oil, blue tape, 600 grit sandpaper, a steel wire brush for cleaning the nozzle, MEK, Magnalube for Z-screws, and a thin palette knife for removing prints.

Top 10 FFF 3D printers

  1. Artist’s choice: Ultimaker 3
    The printing quality of the UM3 is unrivaled and this being the third machine, the Dutch engineers have further perfected the extruder system. It has a 8 inch cubed build size and the only perfectly working dual extruder system with interchangeable heads that retract when the other is printing. Also electronics are of great quality with open-source firmware. This is the only printer that can produce objects that are nearly smooth enough for artistic display. It comes with a pricetag of over $3,500.
  2. Designer’s choice: BCN3D Sigma
    A great quality dual-head printer. You can consider it the UM3’s little brother, except for the 8 x 12 x 8″ build size, at a lower pricetag and less features.
  3. Engineer’s choice: Wanhao Duplicator s5 Mini
    Wanhao is the only Chinese brand that has created a great reputation and a separate USA based office. After the success of the Duplicator i3, the s5 comes with a build volume larger than that of the UM3 and Sigma, and great quality prints, with a price multiple times lower and higher possible printing speeds. If time-effectiveness is of prime importance, I recommend using multiple Wanhao machines over all other printers. You can adjust printing properties like speed, cooling and temperature on the fly. The downsides of these machines are that some need minor modifications, plus with proprietary software it can take a while to start printing. Nozzles are brand-specific and there is less online community and support than with the other brands. The extended version comes with a price tag but lets you create objects up to 600mm in height, making it ideal for architects and engineers.
  4. Maker’s choice: Snapmaker
    Having been the most successful 3D printing crowdfunded campaign so far, this compact printing partner has yet to prove its mark within the 3D printing space. For a sub $500 price it is a steal given that it has interchangeable heads for CNC milling and laser engraving. With specific software it will also be the most plug-and-play of all printers.
  5. Tinkerer’s choice: Velleman K8200 / 3Drag
    This is the machine if you want to experiment with everything a 3D printer can do. It is fully open-source, software that lets you adjust settings while printing, and with an aluminum frame open build with standard components. This lets you transform the printer for low-budget and time investment into for example a food printer, laser engraver or CNC machine. It is fairly easy to control, has a good direct drive extrusion system and therefore very suitable for educational purposes. The BCN3D+ is a slightly better quality but similar type printer at a higher price tag.
  6. Desk rat’s choice: Wanhao Duplicator i3
    For the 8” cubed build volume and quality you get, this is the best value-for-money printer.
  7. Prosumer’s choice: Flashforge Creator Pro
    The FFCP is a great and reliable machine for the beginning 3D printing enthusiast. With a dual extruder, 9” x 6” x 6” build size and 1.75mm filament it is good for numerous applications.
  8. Beast’s choice: Stacker S4
    The truly good way to do multimaterial prints is to employ at least three printheads: two for the dual materials and one for support. The Stacker S4 with a 14” x 20” build plate lets you use up to four heads in one print so you can make a dual-color product with flexible and soft touch features, faster infill if you use a wide nozzle for the second extruder, as well as perfect smoothness with dissolvable support structures.
  9. Innovator’s choice: Symme3D Original+
    Symme3D is a promising startup and has won several international prizes already. Their Delta machines come in different sizes and are customizable in features, supporting multiple extruders, CNC milling, laser engraving, and multiple filament sizes.
  10. Traveller’s choice: Lewihe Play
    If you are purely getting into 3D printing out of curiosity, have little budget and little requirements for your printing projects, this is the machine for you at $69 cost price and 4 inch cubed build volume.

 

About the author: Ralph Zoontjens (1984) is a product designer with a Master’s degree in Industrial Design and 5+ years of studio and startup experience, mostly related to 3D printing.
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