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 This monster is a 3-wing panel raiser bit with back cutter. It will cut the straight bevel, shoulder and flange on the front of the panel as well as cutting the rabbet on the back, all at one time. It is even bigger, heavier and all the more expensive than the rail and stile bit. But, doing this job without these bits would be nearly impossible. The big question is whether or not my router will spin this beast well enough to make these cuts.
 In setting up the bit I found that it just barely fits in the hole in my router table, and that is does NOT fit into the pocket in the fence. Since I will need to make this cut in several passes (because I'm using a 2½ HP router, not a shaper or 5 HP router) the fence will be required. To get around this problem, I cut a series of plywood pieces that can be clamped to the router fence and removed, a layer at a time instead of moving the fence forward -- which I can't do because the raised panel bit will chew up the back of my fence rail.
 It worked! It took a while to do all four panels, nibbling away 1/8" at a pass, but we got it done without tearing up anything. A little sanding and these panels will be ready to install.
 Now the acid test: Does it all fit together?
Answer: no.
The problem is that the back cutter cuts a cove instead of a square cornered rabbet, and the cove is not deep enough to let the flange around the edge seat fully in the groove of the rails and stiles. I had sized the panels to take advantage of the full 3/8" deep groove in top and bottom, 1/16" less on each side to allow for expansion.
Two solutions to this problem presented themselves. One: make the panels smaller so they fit within the frame. Two: Set up the table saw to square up the cove into a proper rabbet. Upon considerable reflection, I decided that messing with the cove cut could cause more problems than it solves, so I trimmed 1/8" from one end and one side of each panel and ran them through the router one more time.
Perfect!
 Now that everything fits, its time to do the finish sanding on parts that will be difficult to get to once everything is glued together. That would include the ogee along the inside edge and the bevels on the raised panels. The flat faces can be sanded more efficiently after they're assembled and the routing completed.
 So, out comes the glue pot and pipe clamps. During the clamping, extra care is taken to be sure the stile ends are flush with the rails and that the frame is square.
These need to set up hard before we work with them again, so it's time to quit for today.
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