3D Printer Components and Build

Main Components of 3D Printers

• 3D printers include key components such as print display, extruder, hot end, cooling fan, 3D print, filament, and print bed.

Build Area

• Build area denotes the maximum object size a 3D printer can create, measured in XYZ dimensions.
• An example of build area size is 8 inches wide (X) by 8 inches deep (Y) by 10 inches high, represented as 8x8x10 inches.
• Large or complex print jobs can be divided into smaller parts for printing and combined afterward.

Filament Diameter

• FDM 3D printers typically use 1.75mm or 3mm filament diameter; the trend favors 1.75mm.
• Machines with Bolden Extruder setups work better with 1.75mm filament.
• 3D printers with Direct Drive setups mainly use 3mm filament.
• Sticking to one filament size is more practical when owning different brands of FDM 3D printers.

Hot End

• The hot end is one of the most important parts of a 3D printer, used for melting plastic and extruding it in tiny layers.
• Important factors for a hot end includes maximum printing temperature, nozzle size, options to change it, and active cooling.

Hot End Types

• Old hot ends were PEEK based, printed one or two materials, and had a temperature limit of about 230°C
• Newer hot ends can use a variety of thermoplastics.
• All metal hot ends can print with available materials, including Nylon, PET, and Polycarbonate.
• All metal hot ends extrude at temperatures above 240°C and have a maximum temperature of 320°C.
• Hexagon all metal hot ends feature active cooling to isolate the melt zone, resulting in cleaner prints due to better retraction and less oozing.
• All metal hot ends have fewer parts, are almost jam-free, and are easy to clean, requiring very little maintenance except when changing filaments.

Nozzle

• The nozzle is the tip of the hot end where the plastic exits, and it needs to be exchangeable.
• Nozzle sizes range from 0.25mm to 0.75mm, with 0.5mm being the most common.
• Changing the nozzle size should be based on design and desired results.

Smaller Nozzle Size

• Smoother Finish: Smaller nozzles produce thinner lines and smaller layer heights for a superior part finish.
• More ridge parts: More, thinner lines create more layers, which can result in the part having stronger bonds.
• More Accurate Prints: Accuracy depends on printer calibration/slicing software, a smaller nozzle size can result in dimensions that are closer to perfect.
• More Detailed Prints: Downgrading nozzle size helps emphasize small features in a design.

Bigger Nozzle Size

• Faster printing, bigger nozzle results in thicker strings, reduces layers, and decreases printing time.
• Better first layer adhesion is due to thicker strings leading to more surface area for the plastic to adhere to.
• Less supports may be needed as bigger nozzles handle overhangs because the ratio between layer height and the extrusion width is greater.
• Better reliability comes due to faster printing and more room for error, resulting in a higher success rate with filaments that have some variations in diameter.

Extruder

• The extruder feeds filament to the hot end, there are two different types of extruders.

Direct Extruder

• Filament is fed from the motor spindle to the hot end, that's mounted on top, this allows finer control over extrusion and is easier to work with.

Bowden Extruder

• The filament is fed form a distance to the hot end, the filament has to travel through a tube.
• Bowden extruders reduce weight, allows for faster movement, and reduces vibrations.
• Bowden extruders should produce more accurate, faster prints
• Bowden extruders require better extrusion and retraction calibration
• It's harder to print certain filaments like Flexible, due to the distance it's oozing more, because the retraction is not as effective.

Cooling Fan

• Cooling is beneficial for most 3D prints, all 3D printing materials require active cooling.
• Cooling fans improve overhanging features, will crisp the edges, and good bridging capabilities.
• Fans vary in size (25mm to 40mm) and design, with some blowing at the mid hot end area and others focused at the nozzle tip.

Heated Bed

• Heated beds are required for high temperature, such as ABS, HIPS, Polycarbonate, and Nylon.
• Heated beds keep plastic warm during printing and prevent warping.
• Heated beds ensure better adhesion between layers for printed parts, crucial for the first layer.
• The temperature usually will be between 40°C to 110°C
• Unheated beds are compatible with PLA based plastics and TPUs
• Beds are covered with PEI, PET or Painters blue tape to which the material adhere.

Print Bed Surface

• The print bed surface helps the print to adhere to the print bed during printing.
• Blue tape works with PLA and NinjaFlex, but better alternatives are available.
• PET 3M tape needs a GOO GLUE for the prints to adhere (GOO GLUE is a SOLVENT OF ACETONE AND ABS PLASTIC), PET tape is easy to replace but more expensive.
• PEI 3M tape works without solvents or glue; has a longer lifespan than most print surfaces.

LCD Display

• Using the LCD display allows you to 3D print without a PC, using software such as Cura.
• The display allows more efficient space usage and is used in the majority of print jobs.
• An SD card is required to read the G-code instructions,

Multiple Extruders

• Multiple extruders allow printing in multiple colors/materials by assigning each extruder a specific color/material.
• The benefit of multiple extruders is setting support structures with a different material that can be dissolved in water.