Fireplace mantel shelf anatomy (floating)

[GaryA]

Do you guys have any ideas or references for the anatomy of a fireplace mantel shelf? We built a house this year, and just have a sealed combustion gas firebox in the wall....going to have someone come in and do cultured stone and a raised hearth around it, but I need to either buy (perish the thought- unless it's cheap) or build a mantel shelf quick (LOML wants it done shortly after Thanksgiving in time for CHristmas). What we had in mind is a traditional mantel shelf (probably about 8-10" deep - it will be mounted to the wall, and about 2" of the depth will be recessed into the stone), molding, painted white, etc.

Can't figure out...is it just a shelf or shallow box, just with 45 degree crown on the front and sides? Can't even really find any plans or project articles that dont do a full blown mantel.

Any ideas?? Thanks!

[Scottydont]

I built one 2 years ago and I had the same frustration. I was surprised how little useable information was on the net. I originally set out to find a plan but later opted to design my own after getting a sense of what I wanted after my research. No plans per-se' but I made the one below with a 30 piece of straight grained 2x8 fir, trimmed in a crown molding and pillars that are a 3 sided box made from 1x4 fir and the front profile detail done with a router. Stained and satin poly'd. The project was much easier than the research!

The original



The tearout, new Durock and Fireplace Insert



The Finished Mantel and tile



The moulding detail

[crokett]

Gary,

I did a new mantel shelf earlier this year. It is a box about 6" high with bullnose trim on top edge and cove moulding on the bottom. I attached it to a brick fireplace by tapconning a ledger into the brick. The ledger is ripped to width to just fit inside the box. I secured the box with screws down through the top into the ledger. It is up high enough that you will never see the screws and it is removeable if I want it to be.

[Ed62]

Not sure if this will help you, but I built a fireplace when I built the addition. The mantle is nothing more than a piece of 3/4" plywood, stained and built up with pre-made moulding. I wanted it to be removable because I have a button switch on the side of the fireplace to turn it on and off. If I ever have to replace it, it will be an easy thing to do. The construction is rather primitive, but it works. The whole thing is basically plywood boxes covered with the thin brick you can buy at the BORG.






Ed

[Stormbringer]

Sorry, not just a shelf, but maybe you could get any idea. The mantel shelf is some one-by pine for the box, 3/4" mdf for the top shelf rounded over and a piece of crown molding that matches the crown profile I installed around the room.

Good Luck
Greg.

[GaryA]

great info...thanks guys! Really appreciate the pics. So, I do have a better idea of the structure that needs to be there now. But, the crown is still a bit confusing to me. When I return the crown (from the front piece to the back wall) do I cut it at a 45 flat on the saw, or replicate the angle it sits at, then cut it upside down/backwards same as ceiling....just having a hard time visualizing this one all comeing together...like you said Scotty. Probably overthinking the research and need to dive in to some trial & error.

[Stormbringer]

When I return the crown (from the front piece to the back wall) do I cut it at a 45 flat on the saw, or replicate the angle it sits at, then cut it upside down/backwards same as ceiling

Same as you would an outside corner on a ceiling installation. Depends though if your cutting it on the "flat" and beveling the cut or in position and just mitering it.

http://www.compoundmiter.com/crown.html

http://www.altereagle.com/How_to_install.html

Good luck,
Greg