Note how the Flexystruder for flexible filament constrains the filament - a PFTE tube confines the filament up to the metal of the hot end. The PTFE is stuck into a long hole. The PTFE is drilled out to 3.5 mm for 3 mm filament.
After the PTFE guide tube is inserted through the plastic extruder body - this tube is drilled (to expose the filament that will go through the PTFE tube) when the Hobbed Bolt hole is drilled out. The hobbed bolt hole drilling punctures through the PTFE tube, exposing the filament that will be driven with the hobbed bolt. See Step 1 in:
Jeff and Brents,
We are hacking your Moarstruder - we have the print files in your first link:
(though the second link is not working -
Can you please point me to your FreeCAD complete assembly of both the Flexystruder and the Moarstruder?
We are building a 2x2 foot printer, so we need a larger nozzle size. Would Moarstruder be able to print flexible filaments as well?
Sorry about that incorrect link, it looks like we had done some internal re-arranging. The full TAZ 6 assembly can be found here: http://devel.lulzbot.com/TAZ/Olive/production_parts/assemblies/taz_full_assembly.fcstd
We do not usually do full assemblies of our tool heads, and unfortunately do not have one available for the Moarstruder or Flexystruder. This is something we may be able to help with in the future, but unfortunately do not have the bandwidth to create them now.
The MOARstruder has shown initial promise in printing flexible filaments. I have personally had success with Cheetah and Polyflex, and suspect with the correct settings will allow successful use of NinjaFlex type materials.
We do have full assembly guides for our Flexystruder and Moarstruder, which may help in modifications you may want to make. Please feel free to look them over here:
One of the items that makes the Flexystruder so reliable, will be the PTFE liner we use to guide the flexible filament. This constricts the filament path, and prevents kinks allowing for greater printing speeds. The one draw back is the PTFE liner cannot go above 245c or decomposition products can be off gassed. A modification like this to the MOARstruder may be possible to create a high output Flexystruder.
We hope this helps, and please don't hesitate to reach out if we can be of any further assistance.
The PTFE liner is used as we found it provided less resistance to the flexible materials than metal components while traveling, which allowed for a greater extrusion speed. We have recently been experimenting with the Titan Aero designs, which allow for flexible and standard printing of materials. It appears they have a very tight feed tube using injection molding, which allows for flexible printing. There may be some sort of middle ground between PTFE and Injection molded.
You can find the full assembly file on the aero here:
Doing some more digging, it appears we made an assembly file of the Moarstruder for our VR simulation. Sorry I missed this yesterday! You can find the full assembly here: http://devel.lulzbot.com/research_projects/animas/simplexy/opah_assy.fcstd
Thank you, and please let us know if we can be of any further help.
Note: See Aero file for the extended feed tube that constrains the filament for rubber printing.