-= GARCAD Cartesian =-

GARCAD cartesian system and accessory tools. Conceive it, deliver it. profit!

    Why use 3mm filament?



    Posts : 16
    Join date : 2017-09-26

    Why use 3mm filament?

    Post by Admin on Sat Oct 07, 2017 11:50 pm

    3mm filament is the only size used by the GARCAD 3d printing accessory.

    Of primary consideration is unloading as much mass from the carriage as possible in order to maximize speed and minimize overshoot due to inertia.
    This means the extruder must be off the carriage and that means a Bowden Tube system.
    3mm filament is much more robust for feeding down a tube from a distance.

    While there seems to be some advantage to 1.75mm filament because it gives a little more control of metering the extrudate, the numbers show that advantage is equal to a 3:1 gear ratio because the volume of material per unit length of 1.75mm filament is only 1/3 the volume of the same length of 3mm filament.
    To meter the extrudate in proper proportion to the travel distance requires @ 100:1 gear ratio.  3:1 is an insignificant and the 1.75mm filament carries the penalty of being more flexible which means that the filament is not solidly shoved into the hotend, but flexes within the bowden tube, storing the extruder's force as compression of filament.  That leads to oozing.  Yet if not for oozing, with inadequate metering, the worse problem of grinding would be the result. (unless the stepper be underpowered and simply skip steps).

    And that's why GARCAD uses 3mm filament (with a Vitamin G extruder!).  Cuz it frikn works best.

      Current date/time is Thu Mar 22, 2018 3:13 pm