Where to start....If you have a working fireplace then check with your fire department or building-code official to make sure the design and materials will meet ordinances in your area. If you have a non-working mantle (like the one pictured) you are ready to go.
Gather lumber....Try using old wood, which offers a vitality and texture. Check out demolition sites, salvage yards and your basement (if you have one). The mantel shown was crafted simply from scraps. [For a 42" x 54" model (outer dimensions), you'll need about 41' of 2" x 6" boards].
Cut & stain...Using a handsaw, cut the planks into 8"-long segments. Vary the lengths slightly to create a casual, stacked look. Color each block to your liking with various stains.
Assemble the frame...Arrange the pieces in three groups (two legs plus crosspiece) according to your dimensions and desired pattern. Use wood glue to adhere the blocks to one another. When dry, glue the three sections together with construction adhesive, following the manufacturer's guidelines. You can mount the whole thing to the wall using construction adhesive as well. Let it set overnight. [Resources: Gorilla Wood Glue and Liquid Nails Construction Adhesive.]
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