How to fix my 3D printer problem?
Here are some of the things that can cause this, listed in rough order from most to least likely.
•The print head collided with something. Maybe something got in the way of the printer, or maybe plastic has been piling up on part of the print and then the print head hit that spot.
•Your printer is trying to move too fast and the motors cannot keep up. Travel (non-printing) moves are usually when the printer tries to go the fastest. Try reducing your travel speed. 70 mm/s is a good starting point for cartesian printers. Delta printers should be able to go much faster (at least 130 mm/s).
•You have some kind of an endstop issue. If an endstop is falsely triggered during a print, then it will cause the printer to think it is now at the 0 position and the entire print will get shifted over. This is usually caused by a loose connection on the endstop switches.
• Your printer is trying to accelerate too fast. Remember Newton's second law F = ma (Force equals mass times acceleration). The more quickly your printer tries to accelerate, the more force (and thus torque) is required from the motors.
•There is some kind of mechanical issue with your belts, motors, and sprockets. If your belts are not tensioned properly, they could be skipping teeth on the pulleys. Also if the set screw on your motor pulley is not tight, it could be spinning on the motor shaft.
•Your motor drivers are overheating. In this case, you will probably notice the motors pausing briefly, as the drivers shut down momentarily and allow themselves to cool. The drivers themselves will be very hot to the touch, and the problem with get worse as the print continues..