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  More Coping: 135° Corners  
After being asked several times about coping these obtuse corners, I decided to play with the task. My observation is: Yes, it can be done. NO, I'd never do it. I think a miter is tighter, easier to cut, and will last if it's glued well and pressure fit. However, to those who would rather cope every inside corner...


This is a small mockup I made at exactly a 135° corner


Unlike a 45° corner, which is really a butt joint when it's coped, the coped piece on this wide corner must overlap the first piece.


I cut the finger or sliver on the bottom about 1/8 in. thick, and notched the first piece to accept the sliver (same thing I did for the 45° corner).


The cope fits pretty tight, though it's still an overlay, not a sharp smooth corner!

Cutting the Cope

POSITION #1: I've developed a slightly better system for using the coping foot. Position #1 is for the first few cuts. My left hand is wrapped over the crown, with my left thumb firmly on/in the hooked bottom edge of the coping foot. This is a pretty safe way to hold the tool!


I backcut this cope much more than I normally would have...


But didn't try to backcut it completely on the first go round.


Instead, I concentrated on cutting a clean cope (it's too easy to wander into the edge when you're back cutting excessively).


POSITION #2: This is the second position, for cutting up from the bottom of the crown. My left hand is on the molding, my fingers reaching for and resting on the jig-saw motor. Remember, if you ALWAYS keep two hands on the saw, you can follow the edge much easier.


Nibble away at the ogee.


I'm still holding the saw in Position #2. I found this technique is easier and more accurate than using the block of wood (see previous article under Tool Reviews). Just be sure to rest the nose of the coping foot against the bottom of the molding before raising the blade into the material.


POSITION #3: This position is really a modified #1 hold. Believe me, the secret to using the coping foot is where you place your hands; how you hold the saw and the molding. My left hand is steadying the molding and the saw, but my left thumb isn't pressed into the hook on the bottom of the coping foot. If I only had a longer thumb on my left hand...


Stand the crown up flat against the jig. Hold the saw in Position #1 and make a series of cuts into the back of the molding.
Then move the blade in short fan-like strokes to remove the waste. The 244D blade is extremely aggressive and works well as a file. I tried a grinder for this operation and found it wasn't as easy to control, made too much noise, and too much dust. Plus, I couldn't get the grinder into the details as easily as I could the jig-saw blade.


Here you can see the crown is clamped flat to the coping jig.
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