how to change staff with 2 voices??

[Kenneth Teh]

I'd like to create tables of scales and patterns for
practice.  Specifically for piano.  Is there a simple
way of creating them?  I tried the automatic staff
change as described in the manual.  It works but I've
run into problems when I introduce the second voice or
in my case, the left hand.

For example, I'd like to typeset the C major scale to
be played for 2 octaves.  Right hand starting a C
below middle C, left hand an octave below and then
going up 2 octaves and returning.  The right hand
voice starts in the bass clef, then switches staff
when it gets to middle C, and switches back again when
it goes below middle C.  Right hand voice have stems
up, left hand stems down.

I have successfully typeset the scale the way I want
it, but it's a complicated input.  I have to put parts
of the right hand music in the left hand part with
voice contexts between << and >>.  You can imagine it
gets painful when I try to do tables of scales and
patterns.

I'm using version 2.6.4 on a Mac.

Ken