I have a Switchwire and have two different accelerometers on the printer. One in the Stealthburner and one mounted to the bed. If I have both installed and configured I found shaper calibrate will use the wrong accelerometer on Y axis.
If both are configured and installed the Y results are extremely bad.
If I only have one accelerometer installed at a time then Y results are a lot more realistic.
This has led me to believe it is using the X axis accelerometer for the Y axis.
So we need a way to mark which accelerometer is attached to what axis in config.
We do have…
#axes_map: x, y, z
# The accelerometer axis for each of the printer's X, Y, and Z axes.
# This may be useful if the accelerometer is mounted in an
# orientation that does not match the printer orientation. For
# example, one could set this to "y, x, z" to swap the X and Y axes.
# It is also possible to negate an axis if the accelerometer
# direction is reversed (eg, "x, z, -y"). The default is "x, y, z".
Not sure if this can be used for this. Also I read shaper calibrate was smart enough to automatically figure the above out by itself without needing to manually configure it. So not sure if what I read was wrong or this is legacy documentation that should have been removed.