Coped joints using oak molding?

[Steve Mathews]

I'm installing a lot of oak base molding in my house and find it hard to cope a joint because of the hardwood. I've done it easily in the past but with MDF and pine. The method I use is the 45 degree cut and cope almost to the cut line. The coping isn't too bad but finish filing to the cut line seem to take forever. Is there an easier way to do this or should I just miter all of the inside corners?

[Art Mann]

I cope to the 45 degree cut line and don't do any filing or rasping. If I make a tight fit, the angle created by the cope allows the wood to compress just a little. That is enough to close a small crack.

[Steve Mathews]

I cope to the 45 degree cut line and don't do any filing or rasping. If I make a tight fit, the angle created by the cope allows the wood to compress just a little. That is enough to close a small crack.

Are you doing this with a hardwood? I don't think oak would compress at all.

[phil harold]

+1
I do this too

I cope to the 45 degree cut line and don't do any filing or rasping. If I make a tight fit, the angle created by the cope allows the wood to compress just a little. That is enough to close a small crack.

[George Bokros]

I had some oak crown installed because I do not do high ladders (foyer is 17' ceiling) the carpenter cut to a 45 then used a Easy Coper to back cut with a saber saw then used a Dremel for the final shaping to the edge and additional back relief.

Easy Coper on Rockler http://www.rockler.com/easycoper-for-crown-molding?utm_source=google&utm_medium=cpc&utm_term=&utm_content=pla&utm_campaign=PL&s


https://www.youtube.com/watch?v=Giv9inaShoE (https://www.youtube.com/watch?v=Giv9inaShoE)

[Martin Wasner]

Cut to line with a jig saw, use a belt sander to got what you can, file the rest.

[Mark Wooden]

Since it's base, flip it over and cut the straight part of the cut with a chop/SCM saw; you can give it a slight back cut by setting the saw to 1/2 a degree. Cope the moulding on the base with a coping saw- with the teeth pointing to the handle, cutting down on the pull stroke.

[Art Mann]

Are you doing this with a hardwood? I don't think oak would compress at all.

Yes, I have used red oak. If you cope so as to leave a more acute angle, the wood will be thinner and more compliant. You are cutting a bevel on the coped edge aren't you? To tell you the truth I have never seen a professional finish carpenter go back and work on his cope with a file or rasp. It is easy enough with lots of practice to cope to the 45 cut line accurately. The part beneath the coped edge never even shows. I have used a sharp pocket knife on rare occasions to try and fix a bad cut.

Edit: I just found a video in which the person cuts the cope in exactly the same way I do in the first minute or so. Notice that he is not making the cut perpendicular to the molding but he is cutting at a slight angle. If your joint doesn't compress to a gapless fit, just cut the angle a little more. Of course, you do have to be able to cut fairly accurately in the first place.

https://www.youtube.com/watch?v=_LukOyO7M_w

[Peter Quinn]

Take a look at this (https://www.youtube.com/watch?v=zDIHtYC_Hik) video. I've seen some of the carpenters we use to supply do a whole house full of crown with this machine. Its expensive but effective. If you take a look at how it works, its basically a table saw head that floats like a key copier. I'm not suggesting you buy one of these, but I know a guy that gets the same basic functionality using a table saw freehand. He uses infeed support to hold the crown level with the table and support long lengths, keeps the blade low so the angle of attack is high. Miter the molding first like a standard hand cope, then at the table saw slowly and gradually move the molding side to side while advancing maybe 1/16" at a time and nibbling away at the waste. You want to come just up to the edge of the miter, you can even highlight it with a bit of pencil. No danger of kick back using the front of the blade, but there is a spinning blade in play so you have to keep careful control over your hands. First time I saw this done I though it was mental, but having tried it, makes coping hardwood moldings much easier. Problem with a hard wood like oak is its strong grain wants to drag the skinny coping blade off course, which results in lots of sanding and filing. Not a joy. You can practice with short scraps to develop a technique and determine if this method works for you.

[George Bokros]

That machine is around $2500 to $3000. I saw it demonstrated about five years ago.

[Tom M King]

Use a sharp no.4 pencil, and cope to the line. Rub the offcut just a little bit. Sharp and no.4 might sound like it doesn't matter, but aim small, miss small. If it's a tight curve, a jeweler's saw works easier than a coping saw.

[Jim Falsetti]

Steve - don't know what profile you are using, but I installed 5-1/4" tall, one-piece, baseboard in my house. The base itself is 4" and the top profile (cap) is 1-1/4". My first attempts (closets, small bathroom and bedroom) were poplar, and I painted it. Very unhappy not so much with corner joints, but the gaps on the walls and the floor were unsightly - nothing is straight - the floors sag and the walls bend. Since the baseboard is 3/4" thick, it doesn't bend to follow the walls. Since the floors are not even, the trim starts off flush, shows a gap in the middle of the run, and is flush at the other end. The other rooms are oak, cherry and walnut trim, so putty and paint were not going to work.

The mill shop foreman where I bought the trim suggested ripping the cap off, installing the straight base with a butt joint (small back bevel when necessary), coping the cap, and adding a shoe molding. It's easy to bend the cap tight to the wall, and the shoe hides the floor gaps. Yes, it is more work, and a little more money, but the results were, to me, well worth the extra effort. Coping the cap and the shoe is very fast. I made a small jig for the band saw to make accurate copes and put the back bevel on at the same time. Test fitting with a couple of small pieces was also helpful.

Anyway, my 2 cents worth.

Best - Jim

[Art Mann]

Jim, that is what they make painter's caulk for. Too many finish carpenters use too much of it to cover their lack of skill but in your case, I would just use it and move on.

[Jim Dwight]

I plan to try a Collins coping foot my next trim job. I think I will have to practice with it but it seems to speed things up a lot and potentially lead to better accuracy versus my normal coping saw. In oak, I would think it would make an even bigger difference.

[Tom M King]

I'll never forget the time I showed a new, young carpenter how to cope baseboard. He had tried mitering inside corners, and of course they always opened up when nailing. I went to the truck and came back with a coping saw. He was down on his hands and knees closely examining the inside corner I just installed to show him how, and he loudly exclaimed, " It looks like it's done growed together!!!!" I said, "Yeah, that's what you want."

Came back to add: That was 25 or 30 years ago. He didn't end up making it as a carpenter, but went into firefighting, and is now Fire Chief in one of the local towns.

[Brian W Smith]

Probably shouldn't post this for a variety of reasons but here goes.......Ya'll do realize that "back in the day",before power mitre boxes that cutting a 45 and then coping the datum was NOT the only,or in most cases the "preferred" method of coping?

Imagine having two doors,and pardon the esoteric'ness...but one is labeled #1 and the other is #2.Today,most folks,heck.....make that pretty much everyone uses door #1.The funny part is not only does door #2 represent vastly more sense,but from an historic sense it is or has,the most worn path through it.This is why I am hesitant to even post.Because I'm not going to tell you how the folks of yore accomplished this task,to the point of not even needing a mitre box.

If it's that important to you....you need to figure it out for yourself.My dad showed me 40+ years ago....his dad showed him.Am posting in the hopes that some will take the time to think seriously about best practices as it applies to how you mark/make a cope.And it has NOTHING to do with a mitre bx.Good luck and apologies to anyone finding this off base.

Edit to add,it's not "scribing" even though that is a time honoured approach.

[Jeff Ramsey]

I use a Nicholson 49 and 50 rasp to clean up copes, along with a utility knife for 90* turns. Both rasps cut through hardwood fine. I also cope to the line (after a 45* cut, and pencil tracing for the profile).

[Art Mann]

Probably shouldn't post this for a variety of reasons but here goes.......Ya'll do realize that "back in the day",before power mitre boxes that cutting a 45 and then coping the datum was NOT the only,or in most cases the "preferred" method of coping?

Imagine having two doors,and pardon the esoteric'ness...but one is labeled #1 and the other is #2.Today,most folks,heck.....make that pretty much everyone uses door #1.The funny part is not only does door #2 represent vastly more sense,but from an historic sense it is or has,the most worn path through it.This is why I am hesitant to even post.Because I'm not going to tell you how the folks of yore accomplished this task,to the point of not even needing a mitre box.

If it's that important to you....you need to figure it out for yourself.My dad showed me 40+ years ago....his dad showed him.Am posting in the hopes that some will take the time to think seriously about best practices as it applies to how you mark/make a cope.And it has NOTHING to do with a mitre bx.Good luck and apologies to anyone finding this off base.

Edit to add,it's not "scribing" even though that is a time honoured approach.

All the really good finish carpenters that I have ever seen use variations of the same coping method being described here. Some use power. Others, like me, use an old fashioned coping saw. All use the 45 degree method to expose a cut line. Are you really claiming that there is an easier, better secret way that nobody knows about? Are you saying that "old" methods are better just because they are old? Why the big secret if you really have something to share?

[Jeff Ramsey]

My Dad, who taught me pretty much everything, exposed a coping cut line with a 45* using a Lion trimmer. He never used a power miter until I bought one. Does using a Lion trimmer qualify as "back in the day"?

[Jerry Miner]

Probably shouldn't post this for a variety of reasons but here goes.......Ya'll do realize that "back in the day",before power mitre boxes that cutting a 45 and then coping the datum was NOT the only,or in most cases the "preferred" method of coping?

Imagine having two doors,and pardon the esoteric'ness...but one is labeled #1 and the other is #2.Today,most folks,heck.....make that pretty much everyone uses door #1.The funny part is not only does door #2 represent vastly more sense,but from an historic sense it is or has,the most worn path through it.This is why I am hesitant to even post.Because I'm not going to tell you how the folks of yore accomplished this task,to the point of not even needing a mitre box.

If it's that important to you....you need to figure it out for yourself.My dad showed me 40+ years ago....his dad showed him.Am posting in the hopes that some will take the time to think seriously about best practices as it applies to how you mark/make a cope.And it has NOTHING to do with a mitre bx.Good luck and apologies to anyone finding this off base.

Edit to add,it's not "scribing" even though that is a time honoured approach.

So Brian---you posted to say you know a better way but won't share it.

[Rick Potter]

Corner (plinth?) blocks. :D

[Mike Schuch]

What is the profile of your molding?

When I had a houseful of pretty plain flat molding with a rounded over top I made a template and used my router to make all the cope cuts.

The template was a flat piece of mdf big enough to support the router base with the curve of the round over cut into the edge. I had 2 mdf guides on the bottom to line up the molding. I would clamp the molding between the two guides sticking out just far enough so that the end of the molding was flush with the furthest point of the profile. Then I would zip over the profile with a 1/4" flush cutting router bit giving me an instant perfect coped edge. All the interior joints mated perfectly.

If a inside corner was slightly more than 90 degrees I would put a 1/4" spacer block between the template and the molding on the opposite side of the template from the profile to give the coped cut a slight taper to cover any gaps.

I always put the back (flat) side of the molding against the template so it would sit square to the jig.

If the molding has a complex profile this method probably wont work.

P.S. I also left the guides protruding slightly from the end of the jig which helped eliminate tearout.