The East 3D Gecko 3D printer uses a clone of the E3D Titan Extruder and a clone of the E3D V6 All-Metal HotEnd. There was trouble while assembling this clone, which I’ve outlined below. From my research it appears to be the same trouble with many clones and not particular to the East 3D parts. The assembly should perform well, but it does require care to ensure a smooth bore through the assembly.
Gather the extruder and hot end parts
Extruder Stepper Motor (1x) C Level Foam
V6 Hot End Clone (1x) C Level Foam
Titan Extruder Clone (1x) C Level Foam
Bag of miscellaneous hardware (1x) C Level Foam
Small heat sink (1x) C Level Foam
2.5mm and 1.5mm hex key, Loctite Low Strength (optional)
The last picture shown here are actually parts provided but NOT used in the assembly. This leads me to believe that this is a generic clone and not one made by East 3D.
Familiarize yourself with the assembly process
Before we get into assembly, I recommend watching this short video to show how a typical Titan and V6 are assembled. This will get you familiar with the parts and pieces we will cover in detail. Note that they are using a black bracket to assemble their system while we will be using the green aluminum part we attached to the X-axis carriage.
Assemble Motor and Extruder Body
Add the small gear to the stepper motor shaft. Dry fit it in place on the X-axis bracket and black plastic extruder body to ensure you have the gear in a good place. I used a 2.5mm hex key as a spacer between the gear and stepper body. The metal gear should be fully engaged with the black plastic gear when dry fitted (don't forget to include the green bracket).
Use a 1.5mm hex key to tighten the grub. Apply a touch of Loctite, if you wish to use it. Tighten it to the flat part of the stepper motor shaft.
Use a short screw and 2.5mm hex key in the lower right corner, under where the hot end mounts, to attach the extruder plastic body to the green frame and extruder stepper motor.
Add in the plastic gear and ensure it is fully seated as well.
Add Hot End and Guide Tube
You may find it easier to work with the hot end by removing the cooling fan and blue plastic part. This should simple snap off the heat sink.
Add the V6 Hot End into the extruder body. It is critical to get this part seated as far down as possible.
A fully seated hot end is the challenge with this assembly and many cloned Titans. It took extra effort to get the hot end to fully seat, as you will see in just a moment.
Add the white guide tube. Again, it is critical to get this part fully seated.
There needs to be a clear and unobstructed path through the extruder gear, the guide tube and the hot end.
Drop in the Filament tensioner
Drop in the black sub-assembly that has the bearing the rides on the filament. Ensure it is fully seated and moves back and forth freely.
Make the tensioner assemble which is the screw, nut and spring and drop those into the assembly as shown.
Note that the tensioner screw is fully inserted into the black plastic extruder body, it doesn't hang out the edge.
Attach clear plastic cover
If the hot end isn't fully seated (or even if it is on the clone), the plastic cover can't be fully seated. It is critical, but very difficult in my assembly, to get the hot end to fully seat in the slot.
I carefully placed a clamp on the plastic cover over the hot end portion. I applied even pressure. This helped the cover and hot end to press into place. I then attached the cover using the long screws. First I attached one or two of the exposed mounting screws, then the final screw or two once the clamp was removed. Note that a shorter screw is used in the corner near the hot end.
When adding the attachment screws, be sure the extruder motor is fully mated to the mount as well.
Even after this process, there is a slight bow in the plastic cover. However I'm confident the parts are fully seated as I can see no obstruction when sighting through the guide tube and hot end.
Add heat sink and cooling fan
There is a small heat sink included with the extruder parts. This should be attached to the back of the extruder stepper motor. I choose to mount my mine on the higher portion of the motor so that it doesn't obstruct the XY belt attachment slots.
Finally, reattach the hot end cooling fan. This should snap into place.