I’m currently doing a remodel and am redoing all the crown molding. My house has a vaulted ceiling and I couldn’t find a reference for cutting the angles with the crown flat on the saw. I searched the internet and you tube, got a crown molding app and even asked a guy at work that used to do interior trim for a living. Finally just figured it out for myself. Took me a while but I have a good formula. It’s kind of lengthy but
If anyone here is trying to cut crown on an angled ceiling and needs a formula, let me know and I’ll post it. 

I'd like to see it!

14 hours ago, Zack said:

let me know and I’ll post it. 

 

3 hours ago, lew said:

I'd like to see it!

+1

This works for getting the mitre and bevel settings to cut the crown molding laying flat on a compound mitre saw.
Rather than try to type it all out, I just attached pics of my notebook.

In practice I’d recommend getting actual angle measurements for each angle in the corner with an angle finder rather than assuming  90 degree corners are actually 90 or the vaulted angle is what it’s supposed to be. The beauty of this formula is that it can be used on the corners of the high wall or low wall and inside or outside corners without changing it. You can also use it for older homes that may not be in square anymore, you just plug in whatever your particular angles and molding widths are.

It takes a little while to work through the first couple corners, but you can do it in about 5 minutes once you get rolling. I keep notes on each corner so if I have another corner with the exact same angles, I just use the settings I already figured.

Thanks Zack. Lots of math.

Why does the crown need to be flat to cut?

I prefer to cut crown flat, it’s a lot easier to hold. Also with a vaulted ceiling your dealing with 3 different spring angles, so you’d constantly be changing out angle stops to cut it in the nested position.

Thanks, @Zack

4 hours ago, BillyJack said:

Why does the crown need to be flat to cut?

Hey Jack, GREAT to hear from you again. It's been awhile. Hope everything is well and you've been keeping busy.

17 hours ago, Zack said:

I prefer to cut crown flat, it’s a lot easier to hold. Also with a vaulted ceiling your dealing with 3 different spring angles, so you’d constantly be changing out angle stops to cut it in the nested position.

That’s true, but sometimes it’s easier to use the indentations on the back of the crown and start there versus using complicated angles..

I guess if I did it for a living, I’d probably cut it in the nested position and develop some shortcuts. Cutting nested isn’t too bad as long as your using the spring angle the crown was made with, but once you have to slide it up or down the table to adjust the angle you lose that nice register. Without using some kind of a stop it’s just to sketchy for me.

It’s all about short cuts.Fastest way to victory…This isn’t the first time this question has come up and a lot of smart people will post a dozen posts on the same topic leading to 50-70 posts in all with confusing answers. I’ll suggest either gluing a couple boards together to resemble the angles to test the crown, or climb a ladder.and test cuts…

8 hours ago, BillyJack said:

It’s all about short cuts.Fastest way to victory

Hmmmm….. Not bad Jack, but I prefer

”preparation is the key to success”.

You can prepare, but believe me you just want to get it done. I crowned for 29 years. Nothing special to me about it..

 

So where are we on crowning?

Edited February 9, 20251 yr by BillyJack

I’ve already done it. Just sharing the formula I used since I couldn’t find one anywhere when I started.

Ok…