SOLVED Titan E3D extruder: strange sequence for material reversing

[JPFrancoia 0]

Hi,

I followed the tutorial here:

https://wiki.e3d-online.com/wiki/E3D-v6_on_Ultimaker_2

And installed a E3D extruder on my UM2. It's also in a direct extrusion configuration (mounted directly on the printhead).

I modified the firmware as instructed, nothing fancy, from the official Marlin firmware:

https://github.com/Ultimaker/Ultimaker2Marlin

I didn't do anything exotic. Everything works perfectly, I can print normaly, change material, etc, but I have one concern:

During the reversing of material (when I want to change material), the extruder reverses a certain amount of filament fast (it lasts for ~3 seconds), then slows down (~3 seconds), then reverses fast again (~3 seconds), and so on. The sequence is repeated a few times.

It wasn't like that before I flashed the new firmware (but the firmware of my UM2 was never updated before, it's quite old).

Is it normal ?

[tinkergnome 926]

I modified the firmware as instructed, nothing fancy

First of all i don't understand, why you would need the change material wizard with a direct drive extruder...? But anyway:

I assume the instructions for FILAMENT_REVERSAL_SPEED and FILAMENT_INSERT_FAST_SPEED are referring to a motor with 200 steps/rev. If your extruder uses the 837 steps/mm from the instructions, i would make a try with halve of these speeds (or even less), and the same for the acceleration, this would be way more healthy for the motor...