Painted mantel shelf w/ crown...best way to construct??

[GaryA]

I'm planning on building a mantel for our Family room. Right now, I've just got a sealed gas 36" fireplace floating in drywall. We're planning on having someone come in and do a curved raised hearth & cultured stone all the way up. Before that can happen though, the mantel needs to be in place. There will be no surround, just the mantel "floating" in the stone.

At first it seems like it would be pretty simple since I am doing it painted white - that I would just basically make a box that was open in the back from MDF. That would be fine if I was doing a more contemporary simple straight mantel. But, LOML wants a crown wrap-around look.

What I'm having a hard time with is, how do I do the crown in this setup? I originally thought build the box, then attach the crown...but what about the top of the shelf with the angle of the crown being offset from the box? DO I just do an "L" shaped support (top & back) and wrap the crown around that? Any input is appreciated. Thanks!

[GaryA]

Anybody have any input on this one? Thanks

[radhak]

Sorry, am having a bad time visualizing this.

Do you have a picture of something similar (or even dissimilar)? Would be easy figuring out from it : don't want this, but could look like that...

I googled, but can't pinpoint what you mean by 'floating in the stone'.

[GaryA]

Good point. I'm just wanting to do a traditional mantel shelf (not with a vertical mantel surround), that would be mounted to the wall, and the stonework would be done around it (similar to attached pic, just not quite as high, different stone). I'm wanting the mantel to be somewhere around 12" deep. The problem that I'm having is visualising how the top of the shelf will look as far as gaps from the "box" structure to the crown. Will I just do a final piece of wood (shelf) over the assembled crown & box structure? (does this make sense?)

[JR]

Will I just do a final piece of wood (shelf) over the assembled crown & box structure? (does this make sense?)

I think you're on the right track.

You'll want to make a rough foundation using 2x4s and/or 2x6s.

Then a nice box affixed to the foundation.

Plan the build up of molding so that the top shelf protrudes beyond the molding. How much it protrudes is up to you - probably 1/2" or so. this is the trickiest and most fun part, finding a combination of molding that you find pleasing.

Now add the shelf to to the box, then build up the molding.

JR

[GaryA]

Great...thanks for the help! What do you think the best way to attach it to the studs would be

[cabinetman]

There are a few ways to do what you want. You could build your box, add any under crown moulding, add the crown and the top shelf sits on top of the crown with a small overhang. On that edge you could rout some profile. To mount, before you add the top, screw the box (it has to have a back) to the wall studs or whatever is in the wall. and then add the top.