Replies

1. 
   Guest_ | May 01, 1999 10:36pm | #1

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   Some crown is not cope-able. Its not the size but the profile. You may have to miter the joints. Ive never run into any that couldnt be coped, but have heard that it exists. Id recommend making some short test pieces at slightly different angles to test the corners first. Good article in an older FHB magazine, check the index.

1. 
   Guest_ | May 02, 1999 12:43am | #2

   *I have also heard this rumour of the uncopable crown although as Charles stated previously, have never seen it myself. Practice at home, buy a couple of pieces if you have to, get it right before you get to the site. Believe it or not I use a porter cable jigsaw and a 4" blade to cope the larger stuff. It is a good idea to map the location, height before putting it on the wall. Filling and shimming is a necessity at walls and ceilings since the big stuff doesn't bend to the shape of the wall or ceiling surface. The reason I say to practice your cuts at home is that you will have to gain a feel for where you have to remove to make an odd angle say 87 degree cope fit. I use a calculator and a bevel mitre guage to get the angles on the chop saw (from which I cope). Practice, Practice, Practice. Please be careful which article you read...trust your own judgement. The only other tip I would add is to consider site lines when deciding which pieces to cope and not. Doorways from and to, where traffic will flow etc. Crown is one of the most challenging things a trim carpenter can get into, g-luck.

2. 
   steve_stacker | May 02, 1999 04:31am | #3

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   The best way to cope crown is to use a 4" or 4.5" grinder instead of a copeing saw you will be amazed. Use 50 grit paper disc on the grinder.

1. 
   Speedcoper02 | Oct 13, 2005 04:29am | #12

   Steve if you think a grinder is the answer.  You haven't tried the Speedcope it makes repetative copes a snap and perfect each time. Cut once and done no filing or rasping. This thing is the trimmers got to have.....

3. 
   Guest_ | May 02, 1999 04:43am | #4

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   dw,

   Just miter it. . .it will be fine. When you say "large", I thought you were referring to 9",12" or 14" crown, I would miter these as well.

   Joseph Fusco

   View Image

1. 
   Guest_ | May 02, 1999 05:38am | #5

   *I have found that mitering the joint then running a pencil lead down the egde of the miter help me to follow the "coping line" easier. Also I have found that if you cope at a steep angle, leaning the saw over 45 deg. the joints tend to fit better.

1. 
   Guest_ | May 02, 1999 07:21am | #6

   *I installed alot of that crown with the built in dental and as far as I could discern, it wasn't copable. I had only 90 degree corners to deal with so it wasn't to bad. I used a bevel gauge to see what the angle was, 90, 94, 86, etc. and I adjusted the miter box accordingly. You can build jigs for other angle corners. I once had to install crown in a room that had an inside 45 angle. I needed 67.5 to get this, I built a fence to go against mine that was 45 and I set the saw at 22.5.

4. 
   Jed_C. | May 02, 1999 06:35pm | #7

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   See the article by John West on this subject in FWW #129.

5. 
   Guest_ | May 02, 1999 11:03pm | #8

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   DW,

   As a general rule, if you are using a crown that is readily available, it will be copable. This is because uncopable crown generally is more expensive to make because it 1. generally needs to milled from stock thicker than normal or 2.generally requires a 5 head molder to be run in one pass.

   All the un-copable crowns I have encountered (and they have been fairly numerous) have been the result of custom profiles drawn by "designers" and architects.

   If you are using a slide compound for your crown, you should definitely read an article by Stephen Nudding circa issue #72 or thereabouts FHB. There is a short sidebar by me adjacent to that article on doing crown the traditional way on a Hitachi 15" chop saw. If you use a jig saw with a 4" Lennox blade (as few teeth per inch as they make and with as wide a set to the teeth - model # in the article-) you will, with a little practice, find the copes easier than the outside corners.

   Good luck.

6. 
   mark_kennedy | May 03, 1999 01:53am | #9

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   Regarding coping large crown. As someone who has installed more than his share of crown including some big crowns I have a few tips for you. First get a quality coping saw, preferably 2 of them. I prefer the type made of flat steel as opposed to a round shank. I have found these to flex too much. Equip it with a fine tooth blade and if you buy two set the blades at opposite angles (this works great for baseboard too). Practice sawing to the line, the less you have to file the better. You will have to backcut considerably, how much depends on the particular crown, a good way to tell is to hold a piece of the crown up in the way it will be oriented to the wall and make sure that it is backcut enough to fit tight to the adjoining piece. This sounds more complicated than it really is. After you make a few copes you will soon figure out where you need to remove material. If you need an extreme backcut it is easier to use a chisel or a grinder to remove material from the back AFTER YOU HAVE SAWN THE COPE. Lastly if you can use a sliding compound miter saw you will have much more consistent results (for 6" crown you will probably not have a choice unless you have a 15" miter saw.) One other thing you may find helpful is to measure down from the ceiling to the bottom of the crown and draw a line so you can make sure the crown is not rolled up or down from its intended angle to the wall. leave the corner unnailed for a couple of feet until you fit the next piece and you can sometimes improve the fit by rolling the crown a little bit to tighten the joint. The biggest tip of all is one word, "patience" Good luck

   Mark

1. 
   dw_ | May 05, 1999 08:23am | #10

   *Thanks to everyone who answered my plea. Lots of good advice. The crown is half up, and even the scarf joints look okay. I've been using a jigsaw, rasp and a huge bastard file I thought I would never actually use. The other lesson I've learned is that no matter how expensive the custom crown is, it still is not neccesarily consistent. Of course, now that I'm cooking on the crown, I've been pulled off onto the walnut built-ins that after five months, suddenly need to be finished by Friday. Same old same old...Thanks again, DW

7. 
   dw_ | May 05, 1999 08:23am | #11

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   Looking for any words of wisdom concerning the coping of joints in large, heavy, crown with a complicated profile. The angles within this remodel vary from corner to corner, ceiling to wall, hovering around, but never AT ninety degrees. I have some experience in smaller stuff, but this stuff runs 6" from the ceiling and has expanded the parameters of the joint beyond my experience. Started stumbling through it on Friday afternoon, would love to show up Monday morning with a plan.