BabyStepping is a very simple idea: allow the user, the ability to tune the first layer height, while the part is printing. This is very effective if the part is printed with a large brim or skirt – you can tune the first layer height to be just right during the printing of the brim or skirt, and then when the main parts starts printing, the results will be perfect.
This requires two things:
For the JGAurora A5/A3S, the community firmware is already configured with babystepping support.
Babystepping can be performed from a computer, while printing via a USB cable. This requires that your host software allows you to input g-code commands during printing - a good program to use for this is Pronterface. In order to do this, you must enter the baby stepping gcode commands: M290 ZX.XX, where X.XX is the distance that you wish to shift the print. Positive values will increase the first layer height, while negative values will reduce the first layer height.
A custom LCD firmware has been prepared by Karl Johnson on the A5/A3S printer facebook group, which adds additional buttons to the LCD control panel. These buttons are accessible from the printing status page (only visible while you are printing from a USB memory stick via the LCD screen). You can download community LCD firmware for both the A5 and A3S printers from here.
I have prepared a very quick video demonstrating this in action:
For information, babystepping via the LCD issues the command G91, then a G1 Z0.025 or G1 Z-0.025 and finally a G90. Therefore babysteps are of 0.025mm at a time. (G90 and G91 just change the positioning method, relative or absolute)