firmware-calculation-steps-mm-example.txt

Here is an example how to finetune X and Y for example.

make sure you know current values you use (check after connecting the values)

For this example I will use X and Y steps p/mm current value of 32.00

Then run a test print for example a low square of 100x100mm 

Then measure the output. for example the print is not 100x100, 
but the printed part is 98mm in X and 101mm in Y.

I always calculate it like this:
- i send the machine 100mm x 32.00 steps = 3200 steps
- machine prints in X 98mm, and in y 101mm.
- so new value for X should be: 3200 / 98 = 32.65 steps /mm
- new value for y should be: 3200 / 101 = 31.68 steps /mm

Change these values in configuration.h to the new ones and upload new firmware to your gen6 board.

#define DEFAULT_AXIS_STEPS_PER_UNIT   {32.65, 31.68, 960, 167}  // default steps per unit x,y,z,e

Then run a new print and verify you made the right changes.

For the extruder this goes simular, but here you need to measure the length of the filament going in.
So you can do a manual extrusion in printrun, make sure hotend is hot / filled etc, 
then at 100mm length make a mark and in printrun fill in 100mm and press extrude button.
then measure the true length and correct value like above.
(note for v10B i recently did more finetuning and current value i use for E steps is 167 steps/mm
(instead of 176 steps/mm)
for even more finetuning you can do 200mm after the 100mm is correct to get it even more accurate.