Video: https://www.youtube.com/watch?v=PqW18kimKDQ
The Delta Hover Extruder combines the advantages of bowden driven delta printers (fast speed and low weight hotend-base/effector) and the advantages of direct drive extruders (no oozing/no needless material). The extruder is hovering about 140mm above the hotend. This shorter distance between extruder and effector decreases the friction and increases the direct traction enormously. With the standard retraction setting of 2-3mm I got no oozing and every time the correct amount of material!
The extruder is centered between the carriages (connected with rubber-band or springs). To reduce the additional weight I have installed a counterweight on the Z-tower connected with a cord and 2 bearings like an elevator. The influence of the additonal weight is nearly zero.
This system is compatible with nearly every existing delta printer bowden extruder!
Partlist:
1x Any existing bowden extruder for your delta printer, I'm using the extruder from schlotzz http://www.thingiverse.com/thing:275593
1x bearing 8mm inner diameter
1x bearing 5mm inner diameter
1x threated rod M8 (length depending on your printer size)
4x M8 Nut for threated rod
1x M5 Screw and Nut for small bearing
1x long cord or flexible filament (length depending on your printer size)
1x some springs or rubber band(s)
Instruction:
1. Print the Delta Hover Extruder parts from here
a) 1x Delta Hover Extruder Roof
b) 1x X-Attachment
c) 1x Y-Attachment
d) 1x Z-Attachment
e) 1x (optional) bearing case for the rod or use 2 flat washer
f) 1x (optional) counter weight container or use a bag filled with the same mass of the extruder :)
2. Assembling:
a) Fix the Delta Hover Extruder roof part with cable ties on the motor of the extruder
b) Place the extruder in the middle above the hotend and connect it with rubber bands or springs to the carriages. Later you have to find out the right length and material of these elements to decrease the vibration of the whole system and to prevent the oscillation of the extruder on fast speed.
c) Mount the Bearing in the middle of the threaded rod (with flat washer or the optional bearing case) and fix the rod with the X and Y Attachments on the printer frame with screws or cable ties, that the counterweight cord on bearing will vertically align with the cord attachment of the Delta Hover Extruder roof part.
d) Mount the Bearing on the Z Attachment and the attachment on the frame at the z tower end.
e) Find any counter weight equaling the extruder (I'm using an additional NEMA motor in a bag). Connect the Delta Hover Extruder and the counterweight with the cord. Check the balance of the extruder and the counter weight by moving the system up and down.
f) Cut off the bowden on the right length that the extruder is about 10mm below the level of the carriages.
g) Connect the Delta Hover Extruder and the Hotend with the bowden
h) Happy printing without ugly oozing !!! :)
Additional you can print my Flex-Filament Adapter http://www.thingiverse.com/thing:1338205 if you want to prevent problems printing flexible filaments.
If you have designed your customized or universal Z Attachment plz let me know.