Anet A8 / Cura : Turning on retraction causes under-extrusion

Hello,

Here is my frustrating problem:
- When I enable the retraction, I get that:

- When I disable the retraction, I get this:


It's clear that the printing without retraction is much smoother and pretty.
So could you explain me this phenomenon ? And possibly help me to solve it ?


I use an Anet A8 (with the default extruder) and Cura 3.6.0, here are my settings:




Here are more pictures of the prints :





I really hope to find a solution to this problem without completely changing the extruder.

Edited 1 time(s). Last edit at 01/30/2019 07:09AM by MinyMine.

Have you tried a smaller amount of retraction? Your screenshot is showing 6.5mm, I'm not using an Anet A8 but I only use 0.1mm of retraction with an E3D V6 direct drive. On my worst case bowden setup, I only ever needed 4mm of retraction and I got that even lower when I made sure the PTFE tube didn't move at all during retraction with a different PTFE holder.

You could always try the extra prime amount after a retraction, as your pictures with retraction almost look like the plastic isn't flowing when the extruder nozzle begins to move around again.

Try changing the retraction distance to 4mm and try again. Tweak this figure until you get the desired results.

And what PDBeal recommend

Thank you for your answers.

I changed the retraction distance to 3mm and that solved my problem !