Word to the wise, don’t set the retraction on Bowden extruders to 2mm
Very Tahitian
I think you forogt to account for the length of the tube…
I used 4.5mm at like 160mm/s if I remember correctly. It’s been a while since I ran Bowden. I want one of each haha
Is there a formula for this? I have been looking and as of yet, never found one! Never found any suggestions on placement of extruder, length of the Bowden tube, tube arcs, retraction settings, lag time, etc… I have been left fumbling in the dark, taking wild guesses!! (0_0)
@Jeremiah_Coley different filaments have different tensile strengths, etc. With that, the shorter you can make your bowden tube the better. When passing filament through the tube, you increase friction (although minimal) on the tube and the distance of filament you are trying to retract/extrude. Position the extruder to keep the tube the shortest.
@Griffin_Paquette Thanks
As a datapoint, the Bukito has a bowden tube that’s only 250mm long, and I use about 3mm of retraction. I’ve always suspected that the geometry of the bend was also a factor, which is why the Bukito is designed to bend the tube in a way that stays more consistent across it’s build space.
As another data point, the UM2 has 700mm of tube. Uses 4.5mm retraction. The UM2+ has also 700mm of tube, but uses 6.5mm retraction due to a different hotend design.
But don’t forget that the Ultimaker has 3mm filament which can make quite a difference when using a Bowden setup
Used to use 3.2mm (?) on my Rostock Mini before switching to Simplify 3D.