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  Beaux Arts Mantlepiece (IBS 2006)  
The Victorian era had run out of steam and many were glad of it. Americans had grown tired of excessive and eclectic ornamentalism just as the industrial revolution changed our country, forever transformed an agrarian society into a world power and an urban culture. The founders of America turned to classicism to express the promise of a new nation based on individual freedom--the Federal Style. So too, architects of the late 19th and early 20th century returned to classical rules, proportion, and structure to express growing confidence in the economic and political power of America.
Well-known architects of the period, including Charles McKim, Richard Morris Hunt, and Daniel H Burnham, studied classical architecture at the Ecole Des Beaux Arts in Paris, adding another name to the new classical revival that catapulted our country into the 20th century. After Burnham organized the Worlds Columbian Exposition of 1893--known as "The White City" for all it's neoclassical designs--the Beaux Arts style appeared in public and commercial buildings throughout the United States. And affluent clients chose the style to express their own social position.

The Fenyes Mansion, built in 1906 along Millionaires Row in Pasadena (just down the block from Greene brother's Gamble House), with its classical facade, pilasters, entablature, and portico, exemplifies the Beaux Arts style. So do many of the mantelpieces within the home.

Most traditional mantelpieces owe their origin to the classical orders, though few are as distinctly derivative as this example. The triglyphs--made up of three shafts, two gains, and six guttae drops, like hanging tassels --are borrowed from the Doric order.

I used the same detail as the principal decoration for the mantelpiece in this article.
Most of the mantel is constructed with pocket holes. The new Kreg Foreman made the job a lot easier. This is an electric pocket-hole machine. Two flip stops flanking the drill bit help center end-grain holes, and they flip out of the way when drilling long boards.
I also used Kreg's new Kreg Clamp--a lot. I mortised the clamp plates flush with my work bench. Here I'm using the clamp just to secure the work piece during glueup. I pocket screwed the sides of the pilasters to the face panels, so no fasteners would be visible.
Pocket screws tend to push the work piece slightly as they're tightened, so I made sure the face panel was a little proud of the sides before clamping the two pieces and driving home the screws.
I repeated the same technique for the opposite side, then used a palm router with a flush trim bit to finish the joint. I'm holding the router back from the cut so you can see how little material is shaved.
Pocket holes secure the top and bottom of the pilaster, too. Don't skip those, they ensure that the pilaster is square. Pocket screws also make it very easy to assemble the face frame of the frieze. Here I'm using the Kreg bench clamp.
Rather than spin the frame around, I used a long hand clamp to secure the opposite side. A router with a 1/2 in. rabbeting bit prepared the back of the frieze for the decorative chamfered panels.
I set the rip fence on my table saw 1/4 in. from the blade, then eyeballed the bade to daylight right near the center of the panel. Don't attempt this without a proper push stick. This is the same technique used for making the panels in the Craftsman-Style mantelpiece.
Seasonal wood movement could cause the panels to split, so don't glue them in. Temporarily tack them in place with a few pin nails shot near the mid-span of the rabbets.
Secure the panels permanently with strips nailed across the back of the frieze, then attach a narrow 1 in. frame to the back of the frieze. Butt joints are fine. They won't show. Just make sure the piece on the bottom runs long. Make the frieze about 2 in. deep, and the pilasters about 4 in. deep, for a 2-in. offset in the crown molding.
Yes, I cheated on the guttae drops. I've watched Frank Klausz' video on cutting dovetails several times, but I haven't figured out the technique, at least not yet. I used my table saw to cut these drops and registered each pass on the edge of the throat guard (right).
Then I flipped the piece end-for-end and lined up the previous cuts with the same edge. The blade passes as close as possible to the previous cut without nipping the end. Triglyps are supposed to have six guttae drops, but I used only five. I could have located a pencil mark on the throat guard, and made the drops thinner, but then they might have been too small to secure with screws.

Finally, I set the rip fence and relieved the drops from the 1x4.

The triglyps are built up from four elements: a 1/2 in.-thick backboard, a 3/4 x 3/4 in. bottom rail, and three 1/2 in. x 1 1/4 in. chamfered shafts. I glued and nailed each piece with 23 ga. pins.
The top rail must be tall enough to allow for the crown molding, which wraps around each triglyph.
Use 2P-10 to secure the guttae drops to the bottom rails.
The guttae drops on the center triglyph hang down beneath the edge of the frieze. Knowing they'd be broken off easily, I secured each one with a 2 1/4 in. trim-head screw.
The other two triglyphs mounted on the pilasters, so I glued the backs--including the guttae drops,
and secured them with 23 ga. pins.
I temporarily attached a block of 1x2 beneath the center triglyph to protect the drops during transportation.
Next I made the moldings in two layers, first beading one edge, then ripping the bead off. Quick-Grip clamps double as feather boards and hold downs. Both are necessary for making these delicate rips.
Use a push stick to finish the cut.
Classical columns have an architrave molding at the bottom of the entablature, right above the capital. They also have an astragal molding just beneath the capital. Mantelpiece pilasters are meant to represent classical columns. Collar moldings help define the sepaeration between pilaster, capital, and entablature. Here the architrave molding is applied in two layers.

I preassembled each set, but there's nothing wrong with attaching them one piece at a time.

Next, scribe a line about 1 in. down from the architrave molding.
A 1/2-in. half-round makes a good astragal molding beneath the architrave. This secondary collar molding increases the drama of the pilaster and the triglyph without distracting attention from either ornament.
Next assemble the pilaster and frieze. Mark dark registration lines across the joint so it's easy to disassemble and re-assemble the pieces for transportation.
Now build the shelf. I made the shelf from two pieces of mdf, figuring the nosing would protect the shelving.
After pre-assembling the first piece of molding, I clamped it down with a Kreg Clamp mounted on a portable plywood table. As the pocket screws tightened up, the shelving is drawn down perfectly flush with the top of the molding. The joint required only light sanding. I owe this trick to Gary Striegler and the Kreg Pocket Hole DVD.
Pre-assemble the second layer of molding and fasten it with glue and 23ga brads.
Don't even think of installing the crown molding one piece at a time. Pre-assemble each pilaster end and you'll have tight and square corners.
Check that each assembly fits the corresponding pilaster, then connect the pieces with the longer frieze runs before installing the crown on the mantel.
The nice thing about building a two-piece shelf is that the pocket holes securing the nosing on the upper shelf aren't visible from beneath the mantel.
Drive a couple trim head screws through the bottom shelf to secure the upper shelf.
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