3D printing and FPV racing drones are two hobbies that pair up perfectly. With a 3D printer, any FPV pilot can produce their own custom products for their FPV multirotors. If you enjoy the tinkering side of FPV, it’s very likely that you will love 3D printing for FPV too.
What is 3D Printing?
3D printing is a material additive modeling process in which a computer aided machine produces a three dimensional object based on a digital file. 3D printing can seem to be a daunting prospect, although, the popularisation of 3D printing has led to the simplification of these machines. In recent years, the 3D printer has evolved into something appropriate for everyday use.
How Does a 3D Printer Work?
A 3D print begins with an STL file. An STL file contains a 3D model with a surface comprised of many tiny triangles. An STL file is inserted into a slicer software, here it is divided into layers and the printing process for the model translated into GCODE. This GCODE is than read by the 3D printer, allowing the 3D printer to physically produce the model enclosed within the digital STL file.
Types of 3D Printer
3D printers are available in many diverse forms and varieties. No particular model is ultimately superior, although each breed does have an exclusive set of advantages and disadvantages. Most printers are a combination of one item from each of the below categories.
An FDM (Fused Deposition Modelling) printer operates by periodically layering thin cross-sections of plastic which, when fully assembled, form a finished 3D model. FDM printers are the most abundantly available models, due to the relative simplicity of their design to other 3D printers, such as SLA printers. Additionally, FDM printers can use a wider range of filaments than most stereolithographic 3D printers.
Both SLA (Stereolithography Apparatus) and SLS (Stereolithography Solidification) 3D printers use Stereolithography to produce a 3D model. This process involves the use of a roving laser to solidify specially formulated resin into a particular shape. SLA printers use liquid resin while SLS printers use powdered resin. SLA/SLS printers tend to be more expensive than FDM printers. Although, SLA/SLS printers are capable of producing extremely detailed prints.
DLP (Digital Light Projection) 3D printers are similar to SLA/SLS printers in construction technique. However, DLP printers use a projected light source rather than a laser to harden the resin. Although the overall DLP 3D printing process is similar to SLA/SLS, DLP is a newer technology. This new technology still requires some refinement and a direct symptom of that is the greater bulk of the DLP 3D printer in comparison to its SLA/SLS counterparts.
Mode of Motion
Cartesian plane based 3D printers have three distinct axis of motion: an X, Y and Z axis, each axis driven by a single or multiple stepper motors utilising a belt or screw system. Most cartesian plane 3D printers utilise a moving bed, although, some more complex design maintain the bed as a stationary component.Cartesian plane printer designs are the most common as their basic design is mathematically simple compared to other systems. However, cartesian plane 3D printers are usually bulkier than other models, such as the delta 3D printer.
The delta style 3D printer has a tower-like shape that sets it firmly apart from other 3D printer designs. Delta printers use a trio of stepper motors in a triangular array to move three individual “arms” up and down. Delta format printers have a stationary bed and have a more compact footprint than cartesian plane printers. If deskspace is at a premium, than a delta printer may be an excellent choice. Delta printers are also capable of higher speeds than cartesian plane based printers.
A polar printer is similar to a cartesian plane printer in terms of motion, although the polar printer uses only one stepper motor rather than two for motion along the Z axis. This allows the polar printer to be less expensive to construct and also somewhat less bulkier than the traditional cartesian printer. Unfortunately, polar printers can only practically be built on a small scale. If the cantilevered extruder carrying axis is too long, the arm will flex. If a large build space is essential, the polar format is a poor choice, however, it is perfect for small scale 3D printing.
3D printers that possess a direct drive extruder are most common. In a direct drive extruder, the extruder stepper motor is located a very short distance from the hot end. The advantage of this system is that the printer has more authority over retraction, which is essential for reducing stringing during printing. However, the presence of a heavy stepper motor on the hot end carriage prevents the printer from achieving potentially higher print speeds.
Bowden extruders differ to direct drive in the positioning of the extruder motor. In a bowden extruder, the stepper motor is disjointed from the extruder carriage, usually fixed to the frame of the printer. Reducing the weight of the hot end can potentially increase the speed and accuracy of the printer. Although, more current is required to force the filament over a longer distance.
Which 3D Printer Design is Best for You?
Every 3D printer design is unique and accompanied by a diverse range of advantages and disadvantages. If you want to get into 3D printing with a low budget and don’t need a large build space, an FDM polar 3D printer is the perfect choice. An FDM delta or cartesian plane printer can provide a larger build space for a greater expense. Finally, if budget is of little concern and print quality an essential prerequisite; stereolithographic printers are the best match for you.
3D Printer Filament for FPV
When producing a model with a 3D printer, the type of filament used is monumentally important in determining the mechanical qualities of the finished part.The range of 3D printing filaments is extremely diverse, each different filament boasts a unique set of characteristics that will not only affect the the 3D printed part, but also the printing procedure.
TPU is a staple of 3D printing for FPV.. TPU is an elastomer (elastic polymer) that boasts a broad spectrum of useful features. TPU filament is tough, durable and flexible, a perfect combination of characteristics for FPV multirotor use. Most TPU filaments are printed with a lower nozzle temperature of approximately 220°C and a bed temperature of 90°C. The flexibility of TPU prevents rapid extrusion, beacause the TPU filament tends to buckle and strangle the extruder gear. For TPU, print speeds of 30mm/s are typical. During the first layer, the nozzle should be given plenty of space between it and the bed, otherwise the extruder may clog.
PETG is a variant of PET, a polymer widely used in the production of plastic bottles. PETG is tough, strong and mildly flexible. For FPV, PETG is commonly used in printing micro sized multirotor frames. The key advantage of PETG over other rigid filaments is its slight flexibility, which makes it a perfect choice for snap-fit parts. PETG is best printed with a higher nozzle temperature between 240°C and 260°C, a bed temperature between 90°C and 100°C is appropriate.
Nylon is an extremely strong and durable material with very strong layer adhesion. Nylon filament is mostly used for printing pods and other structural components for FPV multirotors. Nylon is superior to TPU in terms of toughness, however it has not been as widely adopted due to its expense and high extrusion temperature, which often requires a specially designed hot end. Nylon filament requires a high nozzle temperature of approximately 260°C or greater, a bed temperature between 70°C and 90°C is fitting.
ABS is a cheap, tough and impact resistant 3D printable filament that is also readily available. In terms of extrusion, ABS will smoothly move through the hot end with little risk of clogging. ABS filament is similar to PETG in its qualities, although ABS is not as strong as PETG. ABS requires a medium extrusion temperature of about 230°C – 250° C. ABS has a tendency to warp as it cools, meaning that a heated bed at 100°C – 110°C is necessary.
A slicer is software that is used to translate an STL file into GCODE that a 3D printer can read. GCODE is essentially a lengthy series of the instructions that the printer will follow to create a 3D model. The quality of your slicer software will have an enormous effect on the overall print quality your 3D printer is capable of.
Cura by Ultimaker is a very widely used slicer software. Cura comes loaded with a collection of preset values, designed specifically for the Ultimaker line of 3D printers. If you do not own an ultimaker printer, the option to create a custom profile is available allowing for Cura to be used with any 3D printer that does not require its own proprietary software. The Cura interface is simple and easy to use, print settings are easily manipulated within a customisable scrolling menu. Cura can be downloaded free of charge from the Ultimaker website.
Slic3r is another free to use slicing software. Its function is similar to Ultimaker Cura, although navigation of the interface is not as intuitive as that of Cura. Slic3r can be downloaded from the Slic3r website.
Simplify3D is a paid slicer software that promises to get the most out of your 3D printer. Simplify3D comes preloaded with hundreds of printer profiles, advanced pre-print simulations and other unique features, such as customisable support placement. Simplify3D costs a $149 USD, however, if you are serious about maximising print quality and efficiency, this may be the slicer of choice.
A 3D printer is a non-essential yet remarkably useful tool for FPV. A 3D printer will allow the user to create high quality FPV related items readily and for a potentially lower charge. Another field in which the 3D printer truly shines is prototyping, 3D printers are a great means of prototyping a part before production. If you really want to take the FPV hobby up a notch, invest in a 3D printer.