BLOODWOOD
Botanical Background:
The Bloodwood genus; Brosimum, belongs to the Mulberry family (Moraceae). Local
names include: Satinwood (BR), Conduru (Brazil), Legno Satino (Italy), Satine
Rouge (French Guiana). Sometimes called Cardinal wood. Geographical
Distribution: Tropical South America (Brazil, French Guiana and Surinam)
Variation:
According to wood technologist, Jon Arno, the Bloodwood commercially available
in the United States, is actually cut from several species in this genus and is
highly selected at the mill on the basis of color. Most of the species in this
genus produce rather bland, fine textured, blond woods, so it requires a lot of
sorting to come up with the most vividly colored stock. He further states, an
interesting piece of trivia is that some of the Brosimum species produce edible
fruits...and one of them, the so-called cow tree, produces a latex-like sap
that is actually used as a substitute for mother's milk.
The heartwood is basically brick red in color, without much streaking, while
the sapwood is a uniform blond color. The demarcation between heartwood and
sapwood is distinct. There are no distinct growth ring boundaries through out
the tree. The wood is very dense, .76 g/cm3, more than 30% above the density of
Sugar Maple (.56 g/cm3). The wood is so dense that logs of this wood do not
float. Weight is 56-66 lbs per sq. ft. Trees grow to 120 ft in height, with
straight cylindrical boles clear to 75 ft, and a diameter of from 20-40 inches.
To me, the odor while cutting and sanding is similar to other tropical hardwood
like Padauk and Cocobolo, to which it is not related, though the smell is not
as strong. There is very little residual odor when not being worked.
Working Characteristics:
The Bloodwood has outstanding turning and shaping characteristics. It is
exceptionally stable and has excellent decay resistance. It has a very fine,
even testure. Its striking appearance, and the ability to sand to a mirror
finish, makes it prized woods for use in billiard-cue butts, drum sticks,
Xylophones, organ pipes, showy veneers, inlays various accent applications and
tool handles.
Most Bloodwood commercially available is at about 12% moisture content.
Tangential shrinkage is 5.9%, roughly ½ that of Maple, Radial shrinkage is
4.1%, about the same as Maple.
At the sources I frequent, Bloodwood is available in 4/4 and 8/4 thickness,
widths up to 12” and lengths of 8’-10’, at a cost of approx $13BF.
The heartwood is very resistant to fungi, and insect infestation. The sapwood
is not considered to be durable.
Like most dense tropical hardwoods, Bloodwood can be somewhat difficult to work
with in many important respects. Though there is no silica in the wood to make
it abrasive, the extreme density makes it hard on cutting tool edges, carbide
cutters are recommended for sawing and routing. Machined surfaces are very
smooth, and edges are sharp. The density of the wood requires pre-drilling
before nailing or screwing. Unlike the Rosewoods, gluing is not a problem
because of oiliness, however, because of the tight grain and density, good glue
surfaces are required with a lightly sanded surface recommend. I have used
yellow glue, CA glue, epoxy, and hot hide glue with success.
For turning, a sharp gouge is recommended – frequent sharpening will be
required. Light cuts are recommended, as the wood will splinter if you are too
aggressive. The wood that comes off the gouge is in very small chips, or small
¼” Curls. I have found the Bloodwood takes a scraper very well on the inside of
a bowl, where the wood being cut is supported by the wood behind it. However,
anything but the lightest scraping on the outside of a bowl will result in
excessive tearout.
When sanding, avoid heat build up, as the moderate oiliness of the wood will
cause sandpaper to load up. Bloodwood can be polished to 2000 grit and higher
to outstanding effect. I have seen no tendency to absorb colors from other near
by woods, nor transfer it’s color to other woods. I only dry sand, so I cannot
speak to color transfer when wet sanding. When polished with 1500-2000 grit
sandpaper, because of it’s low moisture absorption, it can be left without any
finish. Oil from the human had will enhance the finish over time. Be warned
that when sanding, that if moisture (sweat) is present in your clothing, the
dust will stain your clothing.
Bloodwood takes all finishes that I have tried, without special preparation.
Oil, Polyurethane, Lacquer, etc. It does not exhibit any of the finish problems
associated with many other tropical hardwoods. Noteworthy, is the fact that,
unlike most of the other red-toned tropical hardwoods, (Padauk, Purpleheart,
etc), Bloodwood does not exhibit a tendency to turn brown or gray, and as such
does not require UV protection.
Information developed by Jon Arno or Mark Kauder and posted by Mark on www.woodcentral.com . Mark has graciously given East Texas Woodturners permission to add the write ups to our site. Thanks Jon and Mark.