I have some crown picture rail in room and have added a door in a corner. The molding design is such that the inside corners of the crown picture rail is generally coped. I can’t miter this, cause one side is already in place, and has been for about 70 years.
So I have to cope this inside crown joint. I spent about an hour Friday afternood experimenting on how to do this. I figured out that I have to flip the crown upside down and do the miter, then do the coping.
My first few experiments were awfull. My coping saw is a dumb one, but holds the blade tight. I just have a hard time getting the cope to match the profile of the corresponding crown. Other than a lot of practice, do ya’all have some tips?
Boris
“Sir, I may be drunk, but you’re crazy, and I’ll be sober tomorrow” — WC Fields, “Its a Gift” 1934
Replies
Depending upon the curve and angle the crown will have to have a variable clearance angle cut away on the backside of the coped piece (you probably have noticed this when checking your fits). Experienced copers can get this pretty close by eye on moldings that they are used to working with. It sometimes requires such an acute cut that it is almost impossible to do accurately with the coping saw. In such cases you have to finish the clearance angles with abrasive tools. I use a 4 1/2" grinder with a sanding disc for the major work on them and then finish up with carving tools and sometimes a rasp. You can do it all with a few half-round and full round rasps and files and enough patience. You will have to test fit the cope and then carve away the parts that are holding the profile away from a good fit. Try to leave the mitered profile on the front face unaltered until the final fitting phase (after the clearance cuts are completed).
Howdy Clay:
I saw you post from three years on the subject and noted with interest your use of a griner with a sanding disk on that post. That seems so logical.
I guess one would have to hold the crown a the same angle as it might sit on the wall, and then back cut (grind) material at about a 45 degree angle to the finished face profile.
I am not cutting the crown on the flat, although I did try that with a miter and bevel, and it looked pretty strange. I even tried figuring out compound miter cuts with my construction master, but I am way to stupid to do that.
So, I fliped it upside down on the fence of my Hitachi CF-8, and just cut a plain miter, without a bevel. The intial cut seems fine. It is just the coping that is a pain in the A S S.
I then outline the profile with a soft dark pencil and then cope away. I am going to try again tonight when I get home on some test pieces, but this is very dificult, and appears to be an acquired skill. I have new found respect for Craig Savage and the other FHB trim carpenters. Regards,
Boris
"Sir, I may be drunk, but you're crazy, and I'll be sober tomorrow" -- WC Fields, "Its a Gift" 1934
a long time ago, i took a crown job with no experience. the first day on that project was a friggin train wreck. i tore all of it down.
that night i cut cope joints on that scrap for about four hours until i had it right.
the next day, the crown coped perfectly, but i got to learn the lessons of 94 degree ceiling corners!
good luck rg
I guess one would have to hold the crown a the same angle as it might sit on the wall, and then back cut (grind) material at about a 45 degree angle to the finished face profile << This is wrong Boris. In some spots this will work but where the curves belly out on the lower side of the curve there is an area where the molding has to be feathered out to almost nothing on some moldings it is a reasonably doable cut and on others it goes to paper thin at the edge. More like an eight degree angle than a 45 degree. Like I said the cut varies all over the place depending on the curvature and the angulation of the molding. You are right about it being an acquired skill. I have seen few copers that did it well on their first try (actually zero). It will help you to use a short offcut that you can hold up easily to check the fit on until you have one that looks good and then you will know what you are working toward. The backcut can be sharper than neccessary with no ill effects but if it is too blunt it will keep you from closing up the joint. It is quite easy to adjust the profile whatever little bit is neccessary after the backcut is made. The clearance cut (or backcut) is the tricky part.
Sounds like you are trying to cut your miter on the flat which is not accurate enough to get a good cope line to cut to. Trying to set bevel and miter makes 2 variables just setting miter makes it more accurate. If the crown is not too tall for your miter saw stand it up with your wall angle against your fence and cut at 45 then pencil face edge of crown, to help see the cope line better, cut with coping saw you will have to use a pretty hefty angle for your back cut and finish with a sharp utility knife to pencil line on face test fit and cut to length.If this peice is small predrill nail holes and pray and attach. Have fun!!!!!
Can't offer any real advice on coping per se, took me a lot of time and I am only half way decent.
Do you have to cope both ends?
If not I always cut the piece I need long so I can chop off the bad cope and start again if I screw up. Then cut to length
Never be afraid to try something new. Remember, amateurs built the ark, Professional build the Titanic.
If the original and the crown you're adding are the same profile start by cutting your new piece with a bevel like you were going to miter the inside corner. The bevel cut is now your guide as to what needs to be removed, with plenty of back relief.
see FWW # 130 - installing crown molding
Place crown upside down on miter saw table, make sure back sits flush against table and fence. Miter like an inside corner. Use saber saw with a fine tooth blade to cut the cope. Clamp crown to fence any way you can. With saber saw base set at 90 degrees , you place base of saw on mitered cut. This will back cut 45 degrees.There usually are two flat spots on crown, they must be cut paper thin. Start with these two cuts, then cut relief cuts where you think you may need them. Cut cove and ogee last.By cutting close to the line you will have a small amount of sanding to do. The profile after cutting should look like a sharp edge, if not , sand the profile , you do not have to sand the entire back cut.Test with a small piece of crown held at a 90 degree angle.Most of the time when cope does not line up it is because the flats are not thin enough.
Good luck Mike
Mike
Good post.
I'm so going to try your method. I have a big crown job coming up.
Thanks,
Be crowned (ouch)
Namaste'
Andy
PS..Whattya think of the crown attachment for the jig saw?
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Andy...
I think you are talking about the collins coping foot. I just bought one online from collinstool.com late last week. Have big crown job coming up in a couple weeks. Will let you know how well it works.
Denny
Andy, I have never used the coping foot attachment, I"ve never seen it to be honest with you except in advertisements. I use a bosch barrel handle sabersaw, the base sits nicely on the cut edge. Try it without the attachment, it always worked for me.
Mike
I am not sure i know what you mean by crown Picture rail . i know what picture rail is . i know what crown is . most of the picture rail I have seen is a simple peice of flat stock. But I wouldn't be suprised that there was such a thing. But if your talking about crown in the corner of the ceiling and the wall. You don't need the angle of the crown exactly. It Maybe it as simple as bringing a level pencil line over, from the bottom edge of the piece up there already. Even if your ceiling isn't perfect all the way across . Then you can rest your bottom edge of new crown on that line.thats your reference. The closer it is, at your joint the nicer the cope will be.
Set the bottom edge of your crown on this line as close as you can get. Once you have it in place. you can pin it with a couple of finish nails, to free up your hands. If you have some help. Hold it up there against the line.I have done this alone already. Level can be irrelevent in the middle of a wall with a belly, but at the joint make it level .
Take out your scribe. (I have an old school compass I like) and scribe the profile of the existing crown. 2 important points: make sure you keep both points of the compass on the same level horizontal plane as you're scribing.
Also, you need to be able to make your points wide enough that you don't run out of compass. Bigger crown bigger compass It is uncomfortable to scribe with it spread apart too far.You could, cut it , the crown moulding, on an angle to get it closer, to your existing piece . If its not very big crown mouding, You may not need too. Scribe away.
Pull your temporary nails. Lay it flat on its back on your Bench. You could trim it close to the line with your chopsaw if you wanted. to give you easier access with your coping saw. It may not be neccessary. It is just an extra step. Then simply cut along the line, Keeping your blade angled. so the back side of the peice is shorter than the front side. In other words you want your pencil line to be on the leading edge. The back cut makes it easier to fit. For tricky profiles, it might be easier, to hog it out with your coping saw . Then straighten things up with a utility knife I have one with a fixed blade. Don't forget your 4 in hand. Thats what I do. And it works for me. You might have to make adjustments. I'm fussy.
Edited 5/10/2003 9:31:03 PM ET by MuleSkinner
For outside corner Mitre's When Your working with big stock, Its nice to have a big chop. I use a delta 10" standard chop saw. If you have a 6"wide peice of stockyou need 3" depth to your arbor. You can get a little more than that out of a 10", the problem I have is the fence.
When I am cutting an outside mitre . I make sure the supports are flat every time which hold the stock. Then i lay it up against the fence, and mark the aluminum saw table base, with a pencil mark. This gives me a registration mark, in case I need to twweek it a little. I leave the piece long, when I cut. Then, I only take off as little as possible till I know it is right. I always cope the other end first. If neccesary. just thought i'd throw this out there. In case I can't remember. I'll need to come back and look it up. Sort of a note to myself. I keep Cutting it , and cutting it, and it's still to short.
I have never heard of a crown picture rail before, perhaps different areas of the country call things by different names. I am assuming that you are referring to a crown molding which is installed up against your ceiling. I must also assume that the mill on the crown you are currently trying to cope is the same as the mill on the crown you are trying to cope to. If the mills of the crown molding do not match exactly then this is going to be even more difficult to do.
You must always cut crown molding upside down and backwards. You need to cut your crown molding on a 45 degree angle to expose the profile of the millwork. Next I take my table saw and run the crown across the blade, removing the material up to the profile line. Next take out a sharp file and file where needed to give yourself a perfect cope line.
I have also relief cut copes with the table saw, but only shorter pieces. How to control when long(er)?
Ken Hill
I will control the longer pieces with a roller, or some other support placed behind my table saw to allow me to work the molding into the table saw blade.
This is a picture rail. And yes it is crown. Very very old home; they used crown as a picture rail. Pictures back then were hung with "picture hooks", either fancy "S" shaped flat brass, or simple large "S" Hooks. Hooks would attach to the top of the crown by hooking over it. Picture rope (actually cord) would attach to the hook; and the cord attaches to the picture.
The rail typically is at the height of the top of the door head casing, and is returned into the head casing, so the same crown is used at the top of the head casing as around the room.
I've burned up about 15 feet of crown doing test copes. What a pain. So far the best technique that is working for me is just a dumb coping saw. An extreme back cut seem absolutely necessary, and one can not get that with jig saws or table saws. A sanding disk, belt sander, or grinder fit with a sand paper helps clean up the mess in back. I have a couple double copes coming up in other rooms, with copes on both sides to look forward to.
Thanks, guys!
Regards,
Boris
"Sir, I may be drunk, but you're crazy, and I'll be sober tomorrow" -- WC Fields, "Its a Gift" 1934
Can't quite visualize the picture rail as crown thing. It's gotta be down from the ceiling a bit so the picture hook can slip over, right?
Some profiles, if they are too round, can't be coped. I haven't seen a picture rail that was that extreme, but some have been close.
Hey, you've got to pull out all of the stops when doing tough crown...jigsaws, files, grinders, sandpaper on dowels. I got a great smart coping saw from Highland Hardware. Eclipse, but I can't find it there now. If you really need one, I got an extra.
Learn to be non-electric... EliphIno!
bb,
i ordered some recently from them for my kids. they don't say eclipse in the catalog, but the ones i got were. i believe they were listed as "english" or something.
fwiw.
You hipped me to them in the first, and perhaps the second place. I got the Larson Two Cherries brand also, not as good as the Eclipse. Good to know I'm not going nuts...
Andy, I have used the coping foot briefly, it seemed like more of pain than a boon. I do like Mike, just ride the factory base on the 45° miter cut EliphIno!
I skimmed all of the posts here and did not see if anyone had mentioned the "CopeMaster". The owner of one of my local millshops (CT) created this tool for cutting crown that pretty much uses the technology of a key cutter. He developed and patented this tool and sells them (for I believe around $1500). The tool looks and works great in demo and would have to save a production trimmer a huge amount of time.
I am wondering if anyone out there has heard of this, or for that matter has bought one and used it.
Bill
Bill
you say this tool cost $1500 bucks! Thats a lot for a tool that copes.
I cope everything with a right angle grinder and it works great. Cost me less than a C note. I bet I can cope damn near anything and still have the $1400 and some change.
Doug