If you wanted it finished at 212mm you would have to start at the next regular size up in sawn sizes which is 225 or 9" in old money.
Nominal size is the size of the sawn timbers
Finished size is the size it ends up once it's got through the planner.
Nominal size is the size of the sawn timbers
Finished size is the size it ends up once it's got through the planner.