Again, using Glen Huey's feature article in the most recent issue of Popular Woodworking, let us look at the second level of molding: a cove and ovolo.
The steps first:
and the final product.
This profile is a little easier to digest. There are two arcs so there are two profiled planes used along with the rabbet. In this case a #4 hollow cuts the 90 degrees of the ovolo and a #6 round cuts the 60 degrees of the cove. If laid out correctly you will be using the #6 until it takes a single full width shaving, no more. The #4 is a little more tricky. You'll have to hold the plane at different angles in subsequent passes. You'll know when you've taken one too many passes with this plane because you'll leave plane tracks on both sides. Stop one pass before that...seriously.
Note: the #6 was used in the previous profile, do you see it? These planes do not cut specific profiles. They cut specific arcs. That's why we're able to do so much with one pair. That's why there's so much overlap in tooling for various profiles.
Why do we start with rabbets?
Why are there chamfers sometimes?
How do I know when to stop?
How is it all laid out? Why?
Answer: Hollows and rounds have no depth stops and no fences and they're difficult to steer.
Stay tuned. We're just getting started.