Guys,
I always cope my crown, but this one has proved a challenge. It’s 7-1/4 with a 45% spring angle – bringing it close to horizontal at several points. As a practical matter, can this be coped? If so, I’ll forge ahead.
Thanks for your input.
FR
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Ouch. Looks tough!
The most useful thing for me when coping is to tip the crown back 90º from the way it will be installed, so that the wall flat is horizontal (resting on a sawhorse or bench), and the ceiling flat is vertical.
Propping it like that makes it easier to tell just how much wood you need to remove.
I achieve that angle by opening the jaws of my clamp-on carpenter's vise until the crown sits the way I want it. Now the cope-cut line is straight up-and-down in theory, but tipps out of plumb a bit in practice for the right amount of back-cut.
No way my little vise would support your crown! But it would be worth it to make a support cradle out of scrap ply or 1x.
I'd cope the crown, getting those problem flats to as near zero as I dared, then hold it up for a test fit, tracing the problem flats onto the already-installed piece. Then put the coped piece down, and make relief cuts in the flats of the already-installed piece with a sharp chisel.
Gary Katz does that to the bottom corner of his crown, and the top corner of his base (go to his website and look at his pics). I don't, feeling that that is overkill.
But in your case, I think you'll have to.
You also might cheat the spring angle just a hair -- 44 to the wall, 46º to the ceiling. I promise I won't tell!
AitchKay
I've never cradled the molding to get a better view of the cope, but it sounds like a good idea. I'll give that a try. Thanks for the input.
I had a similar Crown issue a few years ago. The squared off portion was in the center of the crown. We tried many things with failures. Everything will cope well except where the crown goes to a square reveal.
Ultimately we all used various ways to hand cope but then chisel the square portion so it either fit as if cut at a 90degree or nested together.
Man this is hard to explain. But mainly you may find this has to be done by hand using sanding pads on a side grinder or like I did using a biscuit machine blade on my side grinder and assorted hand tools.
The best time, among 7 carpenters, with our crown was 1 1/2 hours each I.S. corner. I took short of 2hr. Our crow measured 8 3/4" across the face.
Just A Guy With A Hammer
That's right, you could chisel those flats square, too, so that they butt, the same way the bottom corner of my coped joints do. That might be a tiny bit easier than mitering them the Gary Katz way.AitchKay
View ImageWoodcraft sells several micro file shapes either small or large round, triangle and square. They eat wood fast. I like them a lot.
I really like the little beaver I created by mounting a replacement carbide biscuit blade on my small side grinder. It's a scary little wood piranha but it gets the job done faster than those sanding flapper disc.
Just A Guy With A Hammer
Try using an angle grinder with two sanding pads back to back.
Search here for a better explanation.
I've never done it myself but many here swear by it, also I told one of my guys about the technique and he swears by it now.
His question was not, "How do you remove the wood?" It was, "How do you deal with this molding profile?"Two entirely different questions. As he said, “I always cope my crown, but this one has proved a challenge. “ So he knows how to remove the wood.AitchKay
CAGIV,Thanks. I do use my angle grinder to cope alot of the molding I put up, like the guy in the video. Like Aitch said, I just can't seem to get this particular profile to meet flush. I think the consensus is that, it can be coped, but it's not easy. I'll give it one more try using the grinder and the micro-grater rasp that was recommended. This is paint grade, so if I can't get it done, I'll glue and miter the corners. I have this coming up in about two weeks, so I'll follow up and let you know how it went. Thanks for all of your input. FR
I did crown in a couple rooms last summer that I mitred. There were several flat spots that made me decide to do it that way. MDF Paint grade.
There's a bit less leeway in fitting when coped and for sure two guys would make it easier but............it will perform well fitted well and glued. It certainly was shorter in time. Will consider mitreing others as well as the situation presents itself.A Great Place for Information, Comraderie, and a Sucker Punch.
Remodeling Contractor just outside the Glass City.
http://www.quittintime.com/
FR, the crown appears to me to be upside down in the drawing. The ogee concave curve is usually at the top and the convex at the bottom.From your post I assume you have attempted to cope this profile .I use a sabre saw with a blade at least 14 teeth per inch,usually a metal cutting blade. After cutting the miter, I cut with the saber saw square to the base as usual but keep it flat on the mitered cut.This automatically cuts the cope back 45°. You may already know this , bit I'll mention it anyhow just in case.Because of the extra flat steps you would need a few extra relief cuts so you don't bind the blade.I clean up with sanding sticks that I make to fit the profiles.
I think your problem lies where the crown has flat steps,if this isn't very thin then you can't push up the coped piece to fit.Try sanding,chiseling what ever it takes on the piece that did not fit at these steps.If you get it thin ,push up into the installed piece and see if that looks good.
mike
I don't agree that it's oriented wrong. But, it's one of those crowns I'd hold up to the ceiling and ask the homowner for their preference.A Great Place for Information, Comraderie, and a Sucker Punch.
Remodeling Contractor just outside the Glass City.
http://www.quittintime.com/
This is a profile we use all the time. With the horizontal part and the bead , coping at a stain grade is not really possible. Miter it.
View Image
That is similar to one I have used with that bulbous bead at top and at bottom. I made a comment in another thread that there are some crown profiles that CANNOT be coped and have to be mitred and got challenged by somebody who has probably only ever done a simple ogee style.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
I've done similiar where the cut is not consistent and even mitering it is a pain n the neck as the profiles won't line up.
Good millwork.
Don't give in to the miter gang!
orientation is correct.
Last resort - miter the bulb only.
>>The ogee concave curve is usually at the top and the convex at the bottom.<<Most of the time. But historically anyway, you will often see it reversed when it is not at the top of the entablature, as in the position of the bed moulding. Things are so far removed from historical precedent these days that anything seems to go though. This particular one looks like it would look OK either way, but if you flipped it, it would be impossible to cope the resulting small ogee at the top where it turns back under beyond horizontal.Steve
CAGS suggestion was also my first thought. It takes very little practice to get used to it. And it really turns out nice. Here's a video demo I dug up on Youtube.
http://www.youtube.com/watch?v=EijqMNYBsLg
I'm bringing sexy back.
http://www.youtube.com/watch?v=8yIqwyR1ays
That looks much safer than my carbide biscuit blade.
But I've been using saw blades to sculpt and grind for years. Been lucky I haven't lost a leg or hand maybe I'll try a grinder disc next time.
I really like my old excaliber "chainsaw on a disc" wood eater. But it's better for chair seats and scaring girly-men.
Just A Guy With A Hammer
That's how I coped the crown I ran in my last house (my first ever crown job).Speedy... I much preferred it to the @!#!^# coping saw.You still need to file some areas where it's awkward to get the grinder into... particularly transition angles/small spots.I hadn't thought of putting two discs back to back to be able to sand with the "top side" of the grinder... but never really needed to... just manipulated the grinder around.I've seen the collins coping foot in action... and then there's the copemaster too... the copemaster looked simpler.
If paint grade, I would miter it. We miter cut about a third of our crown. That looks like one that would take WAY too much time coping.
Welcome to the
Taunton University of Knowledge FHB Campus at Breaktime.
where ...
Excellence is its own reward!
If the project is new construction, I wouldn’t consider mitering, because frame shrinkage would open up the joints too much.I have played around with mitering inside bay windows, turrets, etc. because of the extreme cope angle. I’ve gone back and forth on this -- currently I’m thinking that I’ll cope the next round.But when I do miter, I’ve come up with this “clamping” trick: about an inch back from the miter joint, drill pilot holes, top and bottom, through both pieces of crown, continuing on through the drywall. Take down the crown, and drive drywall screws into the drywall. Don’t worry about hitting framing or not.Now, when you fit your pieces permanently, butter the miter, wall flats, and ceiling flats of the molding with adhesive caulk, and drive long screws into the pilot holes in the crown. These screws will stop penetrating when they hit the drywall screws beneath, and will start to jack the crown out instead, tightening up the miter joint in a way impossible by other means.You can really fine-tune the joint by loosening one screw, and tightening its counterpart on the other piece of crown. Just make sure that your screws are plenty long, so that the threads are well engaged, and the heads never come close to contacting/damaging the face of the crown. Leave the crown bristling like a pincushion until the glue has set up, then remove the protruding screws.This technique works pretty well, but I still like coped joints better.AitchKay
"But when I do miter, I’ve come up with this “clamping” trick:"That's brilliant! I would never in a million years have thought of such a technique.
BruceT
DW asked why I’m wearing my Dad’s old bow tie, and walking around with such a sappy look on my face, so I showed her your post to me.A few extra dummy slaps from DW, and equilibrium has been restored.Seriously, though, I know that others have played around with related tricks, and one product is currently available commercially, The Copemaster Trim Adjustor:http://www.copemaster.com/copemaster_main.htmlGary Katz reviewed it in FHB, http://www.taunton.com/finehomebuilding/how-to/departments/tools-and-materials/trim-takes-a-spin-copemaster-trim-adjustor-eliminates-gaps-in-bottom-of-baseboard.aspx?ac=ts&ra=fpand here’s my response letter to his review, that FHB didn’t print:*********
The Copemaster Trim Adjustor screw (FHB #193, p. 40) looks interesting. Like Gary Katz, I too used to drive a drywall screw into the bottom plate to use as an adjustable shim, and I had the same adjustment problems that he did.But now I use cabinet-installation screws that have a Torx T-15 drive. Any style of screw will work, though, as long as it's got a T-15 drive. I use a 2" long, ball-detent driver bit made by GRK. It has about 1" of skinny shank just back of the business end that's only about 5/32" in diameter-- plenty of length to reach through most base, and requiring a smaller hole than a trimhead screw.Start by holding the base in position and drilling a 1/8" hole through it, making a pilot hole in the bottom plate. Move the base out of the way, and drive your screw into the pilot hole. Enlarge the hole in the baseboard to clear the driver bit, and you'll be able to adjust the screw in and out with the base in place. This system works with crown,too, which often twists itself a little too flat to the wall while being nailed off. And although coping is still a better way to go, if you decide to miter inside corners when, say, you're running crown around a 45-degree-angle bay, this is a great way to squeeze those miters tight. But of course, as Gary says, heaven forbid.*********
There are pros and cons with both the drywall screw system I posted here, and the GRK system I sent in to FHB. The 5/32” hole for the GRKs, although smaller than the Copemaster’s 1/4” holes, are still larger than I usually like to leave.The 1/8” holes left by the drywall screws are nice and small, but once removed, the joint relies on the glue alone. Although adhesive caulk does provide a fair amount of physical support, I wouldn’t want to rely solely on that for baseboards that will get rammed by vacuum cleaners.So I use the drywall screw method on crown, where smaller holes are more important, and shim support less.AitchKay
Lowe's carry's a plastic angle gauge for under 5 bucks. It does inside and outside corners and its small so it fits into tight areas and your tool belt, its great for crown just pop it into the corner or around the corner bisect the angle it gives you adjust the miter saw, glue your pieces shoot em up and your all done, Its a great tool for five bucks and way better then dropping 150 to 200 bucks on a bosch digital protractor.
One thought to consider. While the crown I said I did was difficult I did do something in one of the rooms where the profile was the same but going to be painted not stained.
I decided as others here have suggested mitre the crown in the corners but I expected problems with shrinkage as well. I determine the exact angle in each corner and cut the crown left side or right side from 2-3 feet long, I back beveled the ends to receive the continuing crown.
I assembled each corner on my bench using biscuits and cross pin nailing. I then installed the corner and continued on fitting the long runs to them. Sanded well and frankly you wouldn't know.
The room was about 40' x 24' with 12' ceilings and oddly shaped with a bump out between each window and fireplace, about 14 inside corners,10 outside. Finished in about 2 days.
since this is painted as well you might consider this.
Just A Guy With A Hammer
from a quick look at it, doesn't look to be cope-able.
I draw a straight line thru ... if the crown profile cuts back into that line ... the cope won't work. Some stuff just isn't physically cope-able.
quick dirty eyeball ... doesn't look possible.
I'd miter.
nothing wrong with a good quality, dead nuts on, miter anyways.
paint grade ... just go for it.
stain grade ... U want an excuse ... prefinish it!
I always miter prefinished stock.
Jeff
Buck Construction
Artistry In Carpentry
Pittsburgh Pa
Don't miter.
That's like giving up.
Before I did that (which i wouldn't), I think I would smash the plastic end off an old Braun Hand Mixer, turn down the blades with a pair of pliers and sharpen the ---- out of them. Put the crown in a vice.
And I would wear eye protection.
And a chin protector.
Edited 1/17/2009 2:46 am by 1muff2muff
My two cents is that it's copable but a difficult one probably and not worth it. If it's pre finished then always miter it. When mitering make sure you always know the exact inside angles. Don't assume they always will be 90.
If you cope, start using the grinder with sanding pads (I use 36 grit) back to back. Hog out the majority and then double back to the fine line like shown in the YouTube video. There's a learning curve, but once gotten, you'll almost hang up your cope saw permanently. Always keep your hand tools like the cope saw, rasps & chisels around to get the nooks & crannies that are too difficult with the grinder. Always clamp the work piece & use 2 hands on the grinder.