A comprehensive educational community devoted to trim carpentry, finish carpentry and architectural millwork. Hosted by nationally recognized author and finish carpentry specialist Gary M. Katz.
  The Collins Coping Foot  
(Click here to visit David Collins' website)
I'll admit it. I've had a coping foot for five years and never read the instructions. When I saw Dave Collins at the last show, and asked him how he made it look so easy, he said: "Gary, did you make this jig?" (see drawaing below). Of course I shook my head, no. "Well you're just like every other carpenter, then. You think you know everything and don't need to read the instructions! Make the jig and you'll never cut crown any other way." I followed his advice--sort of. I made the jig but I still didn't read the instructions. I called him the day before a show, planning on demonstrating how easy the coping foot was to use, but it still wasn't exactly easy. Sure it was a lot better than coping with the crown lying flat, but.... "Dave," I said, "I think I'm using the wrong blade. I've got a real coarse one on here, like you suggested, but I think I need a fine one, like a scroll-cutting blade, but they don't make one long--" that's when he lost his patience and cut me off—I wasn't the only one who had called him with THAT question. "Gary, have you read the instructions yet?" "No." "Well see, that's you're problem. Use the Bosch 244 blade. It's only got 6 teeth per inch, but you're always cutting from the back, so the front will be clean, and the gullets on that blade are deep, which removes the waste fast and clears the kerf quickly, and the teeth are set extremely wide, so the kerf is wide and you can twist that blade around and follow almost any curve. Gary, next time, read the instructions!" After following Dave's advice (I wish I'd just read the instructions!), I couldn't believe how much easier it was to use the coping foot. Here's two techniques for coping Windsor One's Craftsman-style crown molding.
A crown jig is easy to make and doesn't take up much room in my van. The adjustable fence is fastened permanently to the 1x2 cleat, which is secured to the base with screws, so the jig can be changed for different sizes of molding. Both fences are the same height so the molding can be reversed for cutting right-hand copes.


I start by cutting a 45° angle on the end I want to cope, then make a relief cut into the first fillet. You'll notice my finger is on the trigger! THAT'S NOT THE WAY I NORMALLY OPERATE THE SAW--I was shooting pictures of myself while doing this. You'll have more control if you lock the trigger down and move your hand onto the barrel of the saw, closer to the back of the coping foot.
With the molding standing in the jig, you can see exactly how much to back cut—if the blade is perfectly plumb, you're cutting a square butt-cut...So tip the blade slightly back from plumb, with the handle of the saw angled just a little under the jig, and you'll be back-cutting plenty. I keep one finger (or my thumb) on the coping foot, to help steady the tool.


On this molding, start the second cut up high, then angle down into the ogee, turning the corner as much as possible. But don't go too far because the blade won't make it through the whole radius. Finish that cut later, once you've reversed your grip on the saw .


Make all the cuts from the top down, then reverse the saw. Cut in along the second fillet, then back the blade out again.


Now reverse the saw and follow the cove. Tilt the blade forward, pivoting on the single-point of the coping foot, then push the tool forward, climbing up the cut.


Cut a little wide of the profile because it's easy to back the blade down and nibble right to the edge.


Remove the waste from the cove, then nibble into the ogee from the bottom. I find this grip position is the most comfortable and gives me more control. But experiment with the tool to find the position that suits you best.


Each time the waste is removed, you can rotate and reposition the saw blade for the next cut.


Nibble your way right up to the first relief cut. Most people, including David Collins, run the motor at full speed, so control is maximized and cutting is smoother--the saw jumps around less. But I found a few times that slow speed helped me nibble up on the profile line more delicately. Experiment with adjusting the speed of the blade, too, and find what works best for you.


A quick and easy way to finish the cope is with a butt cut on the bottom. To reduce tear-out, I make this cut from the face of the molding.


Then reverse the saw and cut back down toward the bottom again, removing the waste.


Butt cuts are okay, especially for paint-grade molding, but if you want to cut a really clean miter...
Use a piece of scrap to back-up the bottom edge and help control the blade. My hands tremble a lot, so I start the cut with the back edge of the blade riding up and down against the 1x2, then slowly feed the teeth into the molding.


Cut the tip so it's thin, but don't make it paper thin or the sliver will just break off when you install the molding—


or before you even get it up there!


Usually the first piece of crown is up on the ceiling already (so you don't have to hold both pieces in one hand!). Position the cope in place, then score a line across the butt-cut crown, using the sliver as a guide.


Use a utility knife or sharp chisel to remove the waste. Mortise as deep as the sliver is thick.
The finished joint looks like a clean miter and the bottoms of both pieces are flush, without risk of breaking off the sliver.
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