The same thing that happened to my first printer is starting with my second. My first printer had many successful prints using PLA until it eventually started smashing the sensor pads and grinding the motor. Eventually the printer got worse and worse getting more and more problems.
Fast forward a year or so and I decided to get another lulzbot mini. I used PLA again and everything was going great. I decided to try nylon and got 1 good print out of it before it started smashing the sensor washers and grinding the motors. Is there any way to fix this or do I need to send it in for maintenance?