The Goliath is a high-flow hot end designed by Vez (VzBot) in collaboration with Mellow3D. Goliath is optimized for high-speed printing.
Let's look at the main features here:
- 50 mm long meltzone
- Nickel-plated copper thermal block, with built-in 100W 24V heating element
- Heatbreak Bi-material copper-zirconia
- Replaceable PT1000 M3 brass thermistor
- Aluminum heat sink (air-cooled)
- Designed with 9 mm flats for easy nozzle changes
- Uses V6-type nozzles
- Includes a silicone sleeve that withstands 300°C
- Water-cooled variant includes water fittings
- Ability to print at temperatures up to 550°C
The Goliath uses a nichrome wire to heat the block. This wire is quite stiff but can be bent to the desired position. Be very careful when bending. We recommend putting your thumb where the nickel wire exits the heat block to hold it in place and prevent the wire from coming out of the groove and to protect it. Then bend it slowly to the desired shape.
The heat block can be fixed in 3 different positions by 3 screws/holders. You can then rotate the thermal block according to your needs.
On the Goliath printhead, you can move the nichrome wire to the back, under the printhead, or to the right or left side, at the front. Sending to the right will maintain the "natural" curvature of the wire.
Theheatbreak is brittle, but resistant to both abrasion and heat. Difficulties may arise in removing the 'heatbreak from the heatsink. In that case you can push down to the PTFE tube. DO NOT pull hard from the bottom of the heatsink as you risk separating the zirconia throat from the copper section.
You may want to add some thermal paste/grease betweenheatbreak and the heatsink to improve heat transfer. Do not use boron nitride because it will dry out and make it very difficult to remove the heatsink. Silicon thermal paste can be used.
You can also add a thermal insulating sleeve to better protect the nickel wire coming out:
If using the Vz-Hextrudort CNC version with the Vz-Printhead, the PTFE tube between Goliath and Hextrudort should be 22 mm long.
Make sure everything is tightened properly, and once assembled and ready, make 2-3 heating cycles and tighten the nozzle to 1.2-1.4 Nm (if you do not have a torque wrench, make sure not to over-tighten the nozzle so as not to damage the threads of the copper heat block).
The PT1000 sensor should be installed after mounting the silicone sock. It should be tightened by hand or very gently with a wrench. The thread is M3 type, and excessive tightening torque may cause the thread to break.
The silicone sock has a maximum temperature of 300°C. Although the Goliath is technically capable of withstanding up to 500°C, you should always remove the silicone braid if you plan to use it for high temperatures. If it is necessary to insulate it, a fiberglass sheathing can be used.
Notes regarding the nozzle
Always heat the 'hotend before removing the nozzle (retract/unwrap the filament before removing the nozzle). If you do not heat it, the hardened plastic inside the 'hotend will make it very difficult to unscrew and you may damage the 'hotend or the nozzle.
Always tighten the nozzle after heating thehotend. The required torque is between 1.2-1.4 Nm.
The same applies to theheatbreak. To remove theheatbreak, you must first heat thehotend to melt the plastic inside. This operation can be challenging. Wear protective gloves to avoid burning yourself.
Here are the steps to follow:
- Remove thehotend from the printhead
- Remove the Pt1000 sensor
- Remove the silicone sock
- Unscrew the 3 M2 screws to remove the heat sink
- Once the heat sink has been removed and the heat sink is accessible, use a heat gun or blowtorch to heat the heat sink (be careful not to overheat it if using a propane flashlight). The heat should be sufficient to crack the plastic inside so that it is easier to unscrew. If you do not have a heat gun or blowtorch, you can connect the Goliath to the printer and heat it from the printer.
- Use a 5.5 mm wrench or an adjustable wrench. With a 9 mm wrench instead hold the heat block at the bottom.
- Install the new heatbreak. Use 1.0-1.2 Nm for tightening.
What is VzBoT?
VzBoT is a high-speed, moderate-sized 3d printer. Based on the TronXY XS5(A) frame CoreXY, but easily adaptable to other 2020 aluminum extrusion frames.
Since then, the VzBoT project has evolved with CNC-milled aluminum structural components and a custom high-performance hotend. The pace of development of the VzBot project has been lightning fast, and it is now one of the fastest FDM 3D printers around.
Package contains: 1 x Goliath with water cooling - Mellow3D
