"Puckdropper" wrote:

Blackboard chalk would seem to wash off quite easily, not good if
you
want to keep the marks after finishing.

Precisely why I use chalk.

Good for temporary marks such as witness marks for glue-ups or
assemblies, marking the side of a board you do not want to plane,
sand, etc.

Permanent marking is a whole different ball of wax.

Lew