Plywood Tip Assembly for Huxley

From RepRap
Revision as of 07:29, 22 April 2011 by AlexRa (talk | contribs) (Who and why may need this?)
Jump to: navigation, search

Who and why may need this?

This extruder tip assembly was designed (by AlexRa) for use on a Huxley reprap (purchased from TechZone). Since the Huxley feeds filament through a Bowden cable (which does have its disadvantages!), there is no provisions for mounting the extruder drive on top of the extruder tip assembly.

My design goals were:

  • Ensure that the whole thing can be made at home with minimum tools (CNC mill, lathe or laser cutter would make things much easier, but are not required);
  • Avoid using hard-to-get materials (such as PEEK plastic);
  • Make the extruder tip assembly very robust and sturdy.
At the time of writing this, this extruder tip assembly has been made, installed and successfully tested. It appears to work well, but has not seen much use yet, so its long-term performance is not known.

Required materials

When possible, I tried to use materials easily available from a hardware store:

  • 6mm plywood
  • a 30mm wide strip of 2mm-thick aluminium
  • Bronze or brass M6 bolt (could be bought on eBay)
  • Some PTFE tape (the thicker the better, the one I got is 0.2 mm and it works ok)
  • Some 5min epoxy

Some pieces were taken from the stuff that came with the printer (TechZone's Huxley):

  • a piece (about 70mm) of the PTFE tube (the "Bowden cable")
  • a piece (about 5 mm) of the PTFE cylinder used as the tip holder in the original design
  • 25cm of insulated nichrome wire for the heater. The wire that comes with the TechZone kit is just enough for making one heater, so you may need to buy more, or you may prefer to use one of the existing solutions based on a resistor.

Required tools

  • Some carbide PCB drillbits for the nozzles (at least 0.5mm)
  • A Dremel with a drillstand
  • A regular power drill, a drill press would be nice but is not required.
  • Drill bits: 2mm, 3mm, 6mm and 16mm
  • Hand taps (M6 at least)
  • A jigsaw.

==