Ender 3 seemingly speeds up too much on straight long shell lines After few good prints with my new Ender 3, I noticed that prints with longer shell straight lines (> 5&nbsp;cm) have extrusion problems in the middle of those lines.

I figured that this might be because the printing speed (70&nbsp;mm/s) and filament temperature (210&nbsp;°C for PLA). So I increased my filament temperature about 215&nbsp;°C and lowered print speed to 60&nbsp;mm/s. I am using Cura v3.5.1. For the next few smaller prints everything was perfect.

Now I am printing a bigger 128&nbsp;mm X 48&nbsp;mm rectangular shape. In the middle of the 128mm line of the outer shell, I have signs of under extrusion. Looks like dents. 

I also notice that the head is really fast during this 128&nbsp;mm travel. No way ~2 seconds would take 60&nbsp;mm/s to travel 128&nbsp;mm. It is more like 1 second or less.

Why would my head travel at such speeds? 

I am attaching my speed settings.



I am attaching the image of the printed piece and the defect generated.
Your travel speed is set to 120mm/s so it would make sense the 128mm travel takes ~1 second. You most likely have combing turned on so that it doesn't not need to retract on travels. This makes it ooze plastic as it travels and would mimic underextrustion.