Slicer configuration recommendations for bowden extruder

If you are using bowden extruder and you are happy with your prints, could you share what have you changed in your slicer application (Slic3r or Cura) settings compared to the ones used with direct drive extruder? Also, it would be helpful if you could tell us the diameter of the plastic you are using, what type of plastic you are using and if you are using a geared extruder.
I know that there are already some other threads about it, like this one, so if you think this topic was already discussed enough, just post links to other relevant threads in this forum.

The main difference in slic3r settings for a Bowden extruder compared to direct drive is that you need higher retraction. The amount depends on how long the Bowden tube is, and whether it has pneumatic connectors at the ends that move a little during retraction cycles. My Ormerod has 350mm long Bowden tubes, and without pneumatic connectors it needs 4mm. This is for 1.75mm PLA with a geared extruder. My Mini Kossel has a 450mm Bowden tube with pneumatic connectors at each end, and I use 5mm retraction for 1.75mm PLA or ABS. Also with a geared extruder. Both machines give good prints.

The main consequence of too little retraction is blobs on the print.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

@dc42
What hotend(s) do you use and what retraction speed do you use? Do you retract on layer changes? Do you wipe while retracting?

My Ormerod uses the standard Ormerod hot end, which I converted to dual nozzle. The heatsink block that is shared between the nozzles, otherwise it's like two separate hot ends. My Mini Kossel uses an E3d v6.

I have retraction speed set to 45mm/sec, but I think the extruder maximum acceleration has more effect, and I have that set to 1000mm/sec^2. I retract on layer change and do not wipe while retracting (I never tried that setting)..

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

I have about 350mm Bowden tube with pneumatic fittings, and have 3mm retraction.

Quote
dc42
I have retraction speed set to 45mm/sec, but I think the extruder maximum acceleration has more effect, and I have that set to 1000mm/sec^2. I retract on layer change and do not wipe while retracting (I never tried that setting)..

Isn't only 1000 mm/s^2 max acceleration a bit low? I have default Marlin value which is 10 000 mm/s^2.

Small update on my my setup: I have Prusa i3 with a rather long bowden tube (like more than 55cm) (similar to the one this guy has), e3d v6 hotend and an non-geared aluminum extruder. I only print PLA. I have increased retraction from 1mm to 3mm and retraction speed from 30 to 45 mm/s. Also, enabled wiping on retraction, but left retraction on layer change disabled (seems to cause more problems than it solves, especially with fast Z movement). I am pretty happy with the results.