eSun TPU Prusa mini woes  

eSun TPU Prusa mini woes

I've been battling trying to get some decent results out of my Prusa mini with tpu filament. However, I feel like I am now just floundering and need some advice!

I have been trying to dial in settings following this well regarded video: 

I've been using the Cura plugin to make the likes of retraction and Temperature towers, automatically varying the settings as the print goes on.

However, I don't seem to get anywhere near the progress in quality that he does. He too is using a Bowden extruder. I have checked and the temp does vary through the print for example as it should. So I'm assuming the plugin is set up correctly.

Before people suggest, I have been using a filament dryer before and during each print at 55c.

My current settings are: 220-215c, 60c bed temp, 20mm/s, 7mm retraction.

I also have set the extrusion multiplier to 140%. Which I believe to have made an improvement, which I know is high.

I did notice a notable jump in quality when I adjusted the flow factor in the tuning tab on the printer to 150% when the extrusion multiplier was already at 140%. My understanding is that they are the same thing. This produced a print with fewer gaps and a glossier finish. However, it was less flexible.

I then decided to set the extrusion multiplier to 210%, which is obviously ridiculously high, just to see what happened. Leaving the flow factor at 100%. This resulted in the same kind of print with loads of gaps.

In my attached photos these are the two prints being held. I have also attached photos of the car crash of test prints for reference!

Some help would be very much appreciated on this! As I am currently going insane.

Cheers!

(Extrusion multiplier at 210%, flow factor at 100%)

(Extrusion multiplier at 140%, flow factor at 150%)