Damn Cornice, Making Me Look Like An Idiot, Thinks It's Better Than Me...

lee

Afternoon gents.
I'm finishing up a kitchen refit for a customer of mine, and I'm having a bit of trouble with the Cornice. (you guys say "cornice"? the trim that goes accross the top of the cupboards?)

The cornice is huge, and a very decorative concave shape. I've only got a 9" Mitre Saw, and I cant get a cut even 1/4 of the way into it without it slipping or jamming. This means I can't just set a 45 degree angle and chop away. A 12" saw would cure it, but I don't want to buy one to make six cuts.

How can I get a perfect mitre without buying a bigger chop saw?

mdshunk

Rent one or borrow one.

lee

Yeah, I might have to. £55 (about $100) though for one day hire.

mdshunk

I don't know squat about cutting cornice, but I can say this. Part of being a professional is having the right tool for the job. If you don't own it, you need to rent it, and resist the urge to use substandard methods. A craftsman 500 years ago might have been able to get good results with a sharp axe, but we're all high tech now. No excuses.

neolitic

Crown molding,is what we call it. And it's used to form a cornice, if I've got the terminology right. You could do what my Dad did--and he turned out some great work, build a miter box. It's called that cause it is a box. Hardwood like oak works best. Basically there is a bed, and a front and back fence screwed to it. Then you need a good sized back saw and use it to make a precise 45º right, 45ºleft, and usually a 90, thru both front and back fences. You could make the width of the bed to match the "stand out" of your crown. so that the top will rest against the front fence and give you your cut. Worked for a few hundred years before electric ones evolved.

lee

I wish i could show you the molding so you could see what a pain in the butt it is! I normally buzz straight through Cornice and Pelmet at the end of the day, and it stumped me last thing before I went home.

Although I'd love to make a miter box and spend some time with a tenon saw getting it just...right...


...I'm probably just gonna go down to hss in the morning and hire a big bastard dewalt.

neolitic

It's always time or money. Spend some make some,spend some more, and more, and......

aWorkaHolic

Part of being a professional is having the right tool for the job. You end up wasting more time and materials if you have to monkey rig something to do the job. A cheapo miter box will only cost you $5-$10 plus a good sharp hand miter saw $ 15-$35. How much crown are you going to have to buy if you miss cut it? $25-$100.

Go rent a compound miter saw for 4 hrs at around $45.

Joe Carola

What's 100.00 to get the job done right?

__________________
Joe Carola

Trimwerx

Oh man. I love my dewalt 12" chopsaws. The double bevel is the way to go and its well worth the money. I would NEVER do a serious crown job without one. Dewalt has a plus for crown. It has the settings for cutting crown without nesting it. Never use it, but it has it nonetheless. And they last forever. If you're willing to spend the extra $ that fancy table thing they have for it is great too. Adjustable supports and it folds up nicely. The supports also are convenient for spring clamps to hold trim while coping. True it costs $200+, but it's taken a lot of frustration out of the job.

send_it_all

The saw also has provisions for the dewalt "crown stops" (I call them)...the threaded holews in the side of the base for brackets that hold the crown at the height you choose. Pretty nifty.

pkp

I had a saw that actually told you the angles in the manual for cutting crown on flat. I think you set the angle at 31.6 degrees and the bevel at 33.9 degrees.

This is only true if the back of the moulding is at a 45 when it's installed.

Else I think you can use this formula for angles other than 45. I googled this, if that helps

Here's how to figure the miter and bevel using a scientific calculator:
To find the miter angle
1. angle divided by 2=
2. press tan.(answer=X)
3. X x 5.5=Y
4. 3.88 divided by Y=
5. press inv. tan.

To find the bevel angle
1. angle divided by 2=
2. press cos.(answer is X)
3. X x 3.88=Y
4. Y divided by 5.5=
5. press inv. tan.

Trimwerx

Thats exactly what they're called. I need to get some. I can eye it "dead nuts" now but i'm getting older, and things aren't going to work as well, and i'll probably be too proud to admit it.