• So after trying out the Capricorn PTFE tube and seeing the effects of tight tolerances within the PTFE tube I set out to create a bowden extruder with tight tolerances. There were a couple things that I wanted to achieve, one was improving upon my current extruder design by implementing a dual e3d hobb-goblin approach (the hobb goblin on the tension lever has ball bearings inside). The second was a self cleaning mechanism using a dremel cleaning brush (the one in the design is not ideal but was readily available on grabcad but any thick dremel cleaning brush will work). Under the gear brush the surface is sloped allowing debri to slide down into the spring chamber and easily cleaned with an air blast.

    Next I wanted a filament path where the bowden tube gets inserted through the pneumatic fitting all most to the hobb gears (no v cut necessary) this was to prevent the ptfe tube from getting sucked into the gears or grinded and provide a very exact filament path with no room for flexibles to escape. The hobb hears are also completely surrounded by the extruder body to prevent the filament from taking another path.

    The renderings and intended filament to print this with is Acetal POM with any stiff clear filament will do for the lid (I kept the lid thin for best light transmission.), but the body and lid can be printed in other materials.

    I have done motion and interference testing in Fusion360 but still have yet to print and assemble one, I wanted to get the communities feedback before doing so and making the design opensource.

  • I added a couple more renderings, I just noticed that if you look closely at the second rendering, you can actually see the path on each side where the bowden tube ends inside the body and where the filament path begins (the filament path is still encased in the body up until it makes contact with the gears

Log in to reply