On 7/27/2015 4:15 PM, Greg Guarino wrote:
If you wanted to build a face frame whose top member was arched, like this:

https://www.flickr.com/photos/gdguar...in/dateposted/

... how would you form the tops of the stiles? My sense of geometry
tells me that over a 2.5" width, an arc with a radius of 36 feet would
deviate from a straight line by a very small amount. (the height of the
deviation in the middle of the arch is 1") So would you simply cut the
tops of the stiles at the proper angles, leaving the cut straight, or
would you somehow form a very slight curve to mate with the arched rail?

Not difficult at all to make a jig to route the exact arch in the top of
the stile.

You still want the joinery to fit perfectly, both for aesthetics,
strength, and peace of mind.

Think JIG ... and use SU to your advantage:

Print, to scale, a template of the top curve of the part, which you can
then use to both paste on the top of the stiles for the rough cut, and
for making a simple router jig(s) to make the precision fit.

Since you are working on end grain of the stile, build a backup piece
into the jig to mitigate tear out.

Just one, of many ways, to skin that cat. But doing it in such a manner
that is is both pleasing and structurally sound makes you feel better in
the long run.

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