Coping with a router

[wreckwriter]

Hi guys, is a router a good method of coping the ends of trim boards? Assuming so, what type of bit would one need to use and is there a decent/safe way of doing it without having a sled? I only have about 6 pieces to do and would rather not go to the expense of buying a sled, or the trouble of making one. I don't see any more trimwork in my near future.

Thanks much.

Tom

[JimD]

Tom,

I am not sure what you mean by "trim boards". If you are installing base moulding or crown molding in a house, then I do not think you will want to use a router. I cut the boards at 45 degrees which reveals the coping cut that is necessary (at the intersection of the finished surface and the surface revealed by the 45 degree cut). I then back-cut with a coping saw (or you can use a jig saw).

A router would be used, however, to make the mating cut for a frame and panel door that goes on the end of the horizontal pieces. That involves a special router bit.

Jim

[wreckwriter]

Its a plywood beadboard porch ceiling. I'm going to use simple flat molding, sorta like door stop, to cover the gaps at the sides and the joint in the middle where the panels are butted together. At one place there will be a board joining another in the middle at a 90 degree angle. I was hoping to make this joint cleaner by coping the board which will be joining in the middle of the other.

I was looking for an easy way because, to be honest, I don't know how to do it with a coping saw (although I do have one).

[Helmet]

Learn to cope!

I was in a similar situation as you last year. Finally, I looked online and got instructions on how to do it. Its a great skill to have in the bag and one worth learning. I would say a couple of hours of practice, at most, and you'll be good to go.

It will take a lot longer to master, but a little practice and you should be able to get through it.

I would think that a router would be extremely dangerous as you describe. I have tried it with a jig and thought it was a bit tough. The regular, old coping saw is all you need.

Incidently, I have slipped with the coping saw (not that hard to do when back cutting) and gotten minor cuts. Hate to see what a router would do!!!

Good luck and add another skill to your toolbox!

[wreckwriter]

I'm sure you're right. I was looking for the easy way since this porch rebuild project has dragged on for 6 months now. I want to have it finished before hurricane season and my time is severly limited by family commitments.

I'll do as you suggest; it'll be better in the end. Thanks much.

[JSUPreston]

My understanding is that Rockler has a jig that can be used with a jigsaw for coping cuts. I imagine you'd still have to fine tune with a file.

[wreckwriter]

My understanding is that Rockler has a jig that can be used with a jigsaw for coping cuts. I imagine you'd still have to fine tune with a file.

Its for crown molding.

[JimD]

For a flat moulding like a doorstop, I would not cope. I would join the outside corners at a 45 degree angle and but the piece that runs down the center into the sides. Coping is for something with a moulded edge. You cut the reverse of the moulding into the mating piece (you can see the reverse profile by making the 45 degree cut). To get an idea how it works, you can mess with a quarter round moulding (sometimes called a shoe moulding). You can but it cheaply or make some on a router table. Cut a piece at 45 degrees and then follow the line between the outer surface and the surface exposed by the cut with your coping saw. Then butt it against another straight piece. It is not anything magical or even very difficult. For painted mouldings, the guys who built my house left some pretty big gaps (like 1/8 inch) in spots to be covered in caulk by the painter. I like to strive for smaller gaps myself. Clear finish work needs tigher fits. Best to start with painted.

You could use shoe moulding for this project around the edges at least but if the flat looks good to you, I would use simplier joints.

Jim

[scorrpio]

If the moulding lies flat against the surface it will be nailed to, (i.e. baseboard, door stop), you definitely can cope it on a router table, using a straight bit. After cutting the miter, lay its back on the table, and miter cut on front edge will show up to where to cope it.

If the moulding attaches to nailing surface at an angle (like crown moulding), I would not recommend a router.

[cgallery]

Tommy on Ask This Old House used a hand-held angle grinder. He just ground a 45-degree angle on the back of the piece, following the contour. It took fifteen seconds to do a piece of crown, and it was perfect, with a paper-thin edge that fit like a glove. I wish they had old episodes broken into topics and online so I could link to the show, but this trick was impressive.

Thanks,
Phil

[wreckwriter]

A friend suggested I do this:

"I have had good luck with the beaded mullion molding on the main runs. It looks a sight better than lattice. Where they intersect, cut them to a point from the center at a 45 degree angle. That way, when all four of them come together, they will match on the edges, and you won't have an ugly flat joint."

While it sounds really nice I'm not sure my skills are up to all those angles. I have very little experience with miter cuts, the few I have done have been far from perfect.

I originally had planned on using butt joints for everything but the selection of molding around here seems to be almost exclusively rounded or sloping edge stock. I figured a butt joint in the center of that would look funny. I don't need, or even want, anything fancy, just want it to look clean. Its a wooden back porch.

Thanks for all the suggestions, you guys are great for sharing your knowledge!