Tips: what cause step losses and how to address?

Hi there! I'm a huge electronics fan who currently working on 3D printer. Just though I'd like to share something with you. It's so exciting that I ultimately found out what cause step losses and how to address.

Generally speaking, in most cases, while printing, step losses are reflected in split-level of X and Y directions.

Contrast of split-level print and normal print shown in attachments:

The main reason behind is that after the main control board issues an order, the motor does not arrive at the predetermined position, or it moves too fast to make an accurate stop at the position. The moment when a second order is sent over, which is based on an acquiescence of effective execution of the last order (yet the opposite is true), it leads to an error in base point, thus, split-level happens.

The root cause of this problem basically lies in the motor’s false and ineffective following of the main control board’s orders. But what kind of factors exactly will cause the motor’s failure in execution? We analyze from the following aspects:

1. Floppy belt. Too loose a belt could probably contribute to step losses, for instance, if the motor rotates 5 steps but of which, 2 are missing in the belt section, then the actual movement will be 3 instead of the initial 5.

2. Inferior pillow. A poorly-made pillow, rough in surface, could result in great resistance and difficulty in the extrusion head.

3.  Low-quality stepper motor. The output torque may be over small, stepping imprecise.

4.  Above all, the leading factor is a lack of motor strength, largely due to the A4988 drive current shortage. With regard to this, another two major factors may take into account when reckoning about split level, one being if the extruder can come up to the predetermined position, the other being if it’s able to stop there. Only the strength of the motor is large enough, can the above mentioned two factors be attained, especially a pinpoint “brake” of the extruder is critically important during high speed printing.

To address those concerns, ElecFreaks have worked out some solutions. See you next time!