Although my company specializes in high-end jobs with custom trim, it's not often that clients request arched passageways. When they do, I use a simple approach that allows me to efficiently tailor the details to any size opening.
The trim detail I typically use is not a true ellipse; instead, it's a modified form that starts as a tight radius (almost always 12 inches) and blends into a much greater radius at the top, then back into the same tight radius on the other side. Guiding the casing stock through my Woodmaster profile molder (800/821-6651, www.woodmastertools.com...
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