A couple of questions about crown molding

Q1: The foam crown molding we purchased has a very decorative pattern. The pattern is very similar to the third molding shown on this site:
http://www.invitinghome.com/Crown_Molding/Molding_List.htm
While it is possible to match the pattern when making a scarf or butt joint, it is not possible in the corners as far as I can tell. To further complicate matters, several of the corners are something other than 90 degrees (20, 35, 45, etc.). What is the best way to handle the inside and outside corners? Just make the cut and match the best you can? Use some caulk to feather in the mismatched contours? Show guests your new crown molding with the lights dimmed?
Q2: We have bull-nosed outside corners. This means there will be a small gap at the bottom where the molding meets in these corners. Would it be best to cut small quarter round plugs out of 1" thick wood that would slip up into these gaps? Or, does it work just as well to fill the gap with a little caulk, smooth it out, and let it go at that?
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Caulking is usually necessary along the ceiling and the wall to compensate for waviness and can make up for some minor mismatches at the corners. However, you should get the best joints you can no matter what the corner angles are. To do this you must measure the corner angles with a tool like the angle gauge from Starret or similar and then make the cut using a compound miter saw according to the proper settings for that angle. These settings can be found in charts available from a guy named Drake at www.compoundmiter.com. He also sells some angle gauges of his own and has a complete guide book. If you want this job to turn out nice, you need to cut precise angles because even a degree or 2 off can leave a large gap.
Rocky
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I think you missed my point. I am making dead accurate cuts with my miter saw and the angle calculator at:
http://www.altereagle.com/5_How_to_insta.html
I am seeking advise about what to do about the mismatched patterns on the molding in the corners and what to do about the gap on the bull nosed corners.
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wrote:

With molding like you have pictured you probably need to cut inside angles and forget about trying to cope the detail of the molding. That being said, with inside or outside miters you should be able to match the pattern at all the corners. The exception will be on your last joint. To accomplish this you need to start in the least obvious corner and work your way around the room in one direction ending at the same place you started. Once you cut your angle on the first piece, look for the matching are on the next piece and make your cut there. You will probably need to waste the length of one pattern (if that makes sense) to get to the same point to make the next cut.

When we go around bull nose corners instead of making two 45 degree cuts to make a 90 degree corner, we will stop short of the corner and cut a 22 1/2 degree cut then cut a small pie shaped piece with a 22 1/2 degree cut on each side to make the turn then a 22 1/2 degree cut on the next piece to continue down the wall. This takes a little experimentation but makes a nice corner and shares the gap with two small gaps instead of one large one. Going around a 1" radius bull nose, the pie shaped piece will be about 9/16 " across the back side of the bottom of the crown molding. The pieces coming from each direction will hang just past the start of the bull nose radius (almost 1/8") and the pie will fit between.
Mike O.
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Mike O. wrote:

As someone pointed out in alt.home.repair, you can make the last corner joint match by adding an extra butt/scarf joint in the middle of a straight section. It will break the pattern, but the joints will all match.
Chris
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I put up all of my crown molding over the past couple of weekends and I have to say thanks to all of you for your suggestions. Your tips helped me considerably. Of particular help was the tip that I should make a mirror image of the pattern in the corners. All my corners turned out pretty good. Friends and family who have seen my job have been very complimentary. They say it pulls the whole bedroom together.
I truly underestimated how long it would take me. I had about 150 feet of molding and about 20 corners. I spent a tremendous amount of time trimming the pattern to get a mirror image and trial fitting the pieces until I would get the length right. I did discover that the molding's repeating pattern is not a perfect mirror image of itself and when making the cuts, I had to go for best over all fit.
I got pretty good measuring an outside 90 degree corner and getting the length correct in 1-2 cuts. The inside 90 degree corners always took me about 4-5 cuts. The biggest problems were the non-90 degree obtuse corners. I had several of these, 145 degrees, etc. To make things even more difficult, these corners are bull nosed so it made it very difficult to know exactly where the apex of the angle was located, which is where the molding pieces would meet. Those corners slowed me down considerably.
I discovered I have a couple of very curved walls and one very curved ceiling in my house. With the ceiling I had to compromise between a 3/4" gap at the top of the molding, or following the curve of the ceiling resulting in a very visible downward curve in the molding. The molding is painted a dark brown so the curve is especially noticeable. I settled on leaving the gap as the shadow blends into the molding and is not as noticeable.
Is there a tip any of you have to figure out how to reliably measure a cut in an obtuse, bull nosed corner, other than repeatedly trial fitting the molding? There has got to be a better way than trial and error, e.g. shave 1/16" off, see how it fits, repeat as necessary.
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you could cut a block and put it in the corner, then just run the crown to the block. ross www.highisandexport.com
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Ike wrote:

You could cheat and use pre-made corners from that same web site: http://www.invitinghome.com/Crown_Molding/Crown_Molding.htm

Depends on the radius of the bullnose and the size of the gap. Caulk shrinks and sags so it's best left to small gaps. Expanding foam, trimmed flush and spackled, is good for larger gaps.
R
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On Wed, 07 Feb 2007 15:38:06 -0600 Chris Friesen

I did not know it is possible to make cuts so that the joints became mirror images when their is a repeating pattern. I had looked at my test cuts and had come to the conclusion it was not possible. Looks like I need to make a few more test cuts as practice.

Luckily for me, in the largest room with the most joints the crown molding ends at a curved soffit. In another smaller room I'll make the last joint the one in the dark corner.
Thanks to everyone for their very helpful suggestions. I plan to take my time, measure carefully, and make test cuts on some scrap ends I have from a previous project before cutting the real pieces. With a bit of luck I should end up with a job I can be proud of.
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Just being repeating isn't good enough, the pattern has to have a reflection. If you had molding with, for instance, a bunch of tigers on it, all facing left, then it won't work. If one bit of molding is cut through the middle of a left facing tiger, then the other peice has to be cut through a right-facing tiger. (Of course, if it's a zoomorphic pattern, it's going to look a bit strange anyway...)
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The high density foam crown molding (moulding sp?) I am using is C814 on this site:
http://www.architectural-ornament.com/productList.aspx?catId
It does have a repeating pattern, but not one that I am sure a mirror image can be made in all cases. When I click the "Enlarge Photo" button and zoom in on the mitered corner I cannot tell if the seam is a mirror image or has been filled with caulk. Any opinions?
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