Extruder stutter - firmware problem (no replies)

Hello everyone,

I am the proud owner of a prusa i3 Steel, but since I changed the Arduino board (on which the seller had preloaded the Marlin firmware), and uploaded Marlin on the new one, everything works fine appart from the extruder's stuttering. It creates an uneven thread of ABS causing very ugly prints.

I narrowed down the problem to the Marlin firmware, as I checked all the drivers, cables, extruder mechanism.

I had to change the Arduino because for some reason I driver fried, and now the LDO of the Arduino mega 2560 overheats, when connected to USB and the RAMPS 1.4, causing the Arduino to shut down.This does not happen when the RAMPS is disconnected.


For a short while, when I use the original Arduino the print is perfect until it shuts down, which leads me to believe something is wrong with the Marlin I installed.

I went through a lot of threads but did not find a lead on this topic, about what to fine tune on Marlin to ease the extrusion.

I'd be very grateful for any kind of help!

I face now 2 options:
- exchange LDOs, but I'm not sure changing the faulty LDO will repair the original Arduino
- find a way to tweak Marlin