Segmental arches are easier than elliptical arches to lay out on a door slab, and more practical than round arches when there’s limited headroom. (For more on curved trim, see “Building an Arched Passageway,” 12/07). I usually cut out the arch with a straight-bit-equipped router mounted on a trammel arm (see slideshow). But sometimes, with multiple doors, I make a plywood pattern first and use it — along with a router equipped with a long pattern-bit — to make the cuts. If I’m working with an existing doorway, I scribe the slab to the opening for the best fit, since I never assume that I’m working with a true radius or a square opening.
After cutting the arch, I sand the door smooth and carefully remove all the dust. Then I seal the top with 1-1/2- or 2-inch-wide iron-on veneer edge banding. This tape isn’t widely available at most home centers or lumberyards — especially in species other than oak — so you’ll have to do a little advance planning when you’re cutting arched doors.
I usually make my own curved moldings for the parts of the frames that match the door radius. If there’s an embossed pattern and it’s fairly simple, I’ve had good luck matching it with a wood-burning tool judiciously applied to the milled panel molding. For more intricate embossed patterns, I’ve actually stripped out that part of the design from a straight piece of molding and glued it to the curved section. Of course, many millwork suppliers offer curved wood moldings (for doors that will be stained) or flexible resin moldings (for doors that will be painted) to match their straight molding profiles.