wrt groving parting bead
A hand method would be some form of scratch stock. E. g.
Take a stick of hardwood, one by one by eight inches or so. Rip 2/3 of it to
1/2 in. and crosscut that off. The shoulder just made will be the fence that
runs along the side of the bead. Make a steel cutter that you set through the
1/2 in section left, set in centered at 1/2 the width of the bead to be
scratched. The cutter could be the shaped (file, grind) end of a six penny
nail, or some carbon steel--shank of an Allen key, maybe, for examples. Hammer
flatten the cutter first. That will get you an easier piece to final shape.
Tap that in (drill an undersized starter hole) just deep enough so that it is
proud of the stock the same depth you want for your bead slit.
Run it along the bead--which you may have to support on a runner attached to
the bench, don't know, enough times to make the full depth of slit that the
scratch stock allows.
There are variations.