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  Nip & Tuck 22 1/2 Wall Returns  
By Derrell Day, a carpenter from Panama City, Florida who contributes frequently to the JLC Finish Carpentry Forum.
If you ever have that problem where the base is thicker than the casing, and--like me--you hate to see back-cut joints, try this little trick. A little nip on a 22 1/2° wall return can turn a problem into a pretty neat-looking joint.  And while you're at it, remember, 22 1/2° returns--rather than plain old 45 degree miters--work on chair rail, too.
Always start by cutting the return 'cap'--that's the little piece that caps the end of the molding.  Whenever I work with stain-grade material, I cut the cap first so the grain will run perfectly around the miter.  I guess it's a habit, because I cut paint-grade material the same way.  The first cut is a 45° angle.
The 45° miter will kiss the wall, but the other corner will meet the baseboard, so cut it at 22 1/2°. This is Gary's saw...too bad he can't afford zero clearance kerf plates.  I always keep a fresh kerf plate in my saw. They are only about $7.  More on that subject in a minute.
Cut the baseboard at 22 1/2°, too.
Then glue up the joint.  I like using Fast Cap's new 2P-10 glue because I don't have to carry or plug in the gun for my HiPerformer outfit, I don't have to worry if my CB 900 gun has a butane charge, and I don't have to wait for anything to heat up, either (check out my review of this new glue). Gary shot these pictures (which he did okay at), but it's not how I apply the glue.  I run a small bead about 3/16" inside the perimeter completely around the cut. Believe it or not, I have found that it makes for a mechanically stronger joint.
After spreading the glue on one piece of the miter, the manufacturer recommends spraying activator on the other piece.  I don't have the patience to wait even 30 seconds, so I spray the activator right on the glue.
Then squeeze the pieces together. Now this is where the learning curve comes in: Keep your fingers away from the wet glue and keep them moving, or you'll leave more than sweat behind on your woodwork.
Now the corner is ready to be nipped. Gary say's he'd lay the return up against the wall and the casing, like this, then scribe a line on the cap, just back from the face of the casing.  But I've done this enough so that I can judge the nip by eye.
Gary has to nip to that measurement mark every time, which is tedious and time consuming.  If he had a zero clearance kerf plate in his saw (only $7.00), he could have made a mark on the kerf plate and lined up the base with the mark, like I do, then nipped off the end of the cap.  I'm not sure I could afford Gary on one of my jobs.
Either way, you'll have a perfect return that looks like it grows out of the wall AND the casing.  And there's no little hole against the casing like you always get with a plain, old, everyday, 45° return.
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