I've never used Android Studio before until just recently. I installed the latest version, v3.5.3. I tried importing an old Eclipse project and got some errors and it seems that I have resolved all of those after much Googling.
I have heard that the Ender 3 has some problems with the feeder gear tension. There are some mods to make it stronger and more reliable. If the filament slips through the gear on your feeder, that could be a reason for under extrusion.
I have changed the feeder gear into a metallic one.No more grinding the filament.I think the problem lies elsewhere. Everything is perfect except the very beginning of a layer.Maybe I will change the speed to a very low setting so that I can pinpoint where the problem is and go from there.
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