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Bubinga
(Guibourtia tessmannii)
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| Common
Names: |
|
Akume
Bingbinga
Bubinga
Essingang
Kevazingo
Ovang
Waka
|
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- Mechanical Values
| Category |
Green |
Dry |
Units |
| Weight |
65 |
55 |
lbs/cu.ft. |
| Density
(air-dry) |
|
58 |
lbs/cu.ft. |
| Specific
Gravity |
|
0.88 |
|
| Hardness |
|
65 |
lbs |
| Stiffness |
|
2290 |
1000
psi |
| Bending
Strength |
|
22293 |
psi |
| Shearing
Strength |
|
|
|
| Max.
Crushing Strength |
|
10010 |
psi |
| Work to
Maximum Load |
|
|
|
| Radial
Shrinkage (G->OD) |
|
5 |
% |
| Tangential
Shrink. (G->OD) |
|
9 |
% |
| Volumetric
Shrink (G->OD) |
|
|
|
- Environmental
Profile
- The population of the
species within its natural habitat has not been
officially assessed.
-
- Distribution
- The growth range of
the species is reported to be Cameroons, Gabon, and
the Ivory Coast. The species is also reported to
grow in Zaire.
-
- Product Sources
- Some material from
this species is reported to be available from
environmentally responsible or sustainably managed
sources.
-
- The International
Tropical Timber Organization (ITTO) reports that the
species is a regular source of timber for export.
-
- Bubinga is reported
to be available in lumber form on the US market.
Imported logs are reported to be massive, and
may weigh as much as 10 tons.
-
- The following species
in the database is reported to have similar
properties to Bubinga:
-
Muiracataria
(Astronium leicointei )
-
- The following species
in the database has been suggested as a good
substitute for Bubinga:
-
Pao rosa
(Swartzia fistuloides )
-
- Tree Data
- The trees are
reported to be large, often reaching heights of more
than 100 feet (30 m) and trunk diameters of 36
inches (90 cm).
Boles are usually well-formed, and are 30 to
60 feet (9 to 18 m) long.
-
- Sapwood Color
- The sapwood is
whitish in color.
-
- Heartwood Color
- The heartwood is
medium red-brown or red to reddish-brown in color,
with lighter red to purple veins. Upon exposure, the
wood becomes yellow or medium brown with a reddish
tint, and the veining becomes less conspicuous.
-
- Grain
- The grain may be
straight or interlocked.
Logs with very irregular grain are rotary cut
into veneers called Kevasingo .
-
- Texture
- Texture ranges from
fine to very fine, and is even.
-
- Luster
- The wood is lustrous.
-
- Odor
- There is an
unpleasant odor which is noticeable when the
material is freshly cut.
-
- Ease of Drying
- The wood dries easily
with little degrade.
Gum exudation may present some difficulties.
-
- Drying Defects
- The timber may
distort if it is not seasoned slowly.
-
- Kiln Schedules
- T2 - C2 (4/4); T2 -
C1 (8/4) US
-
- Movement in
Service
- The timber is
reported to be dimensionally stable, and retains its
shape well after manufacture.
-
- T/R Ratio
- 1.62
- This indicator is
more meaningful if it is used together with other
drying information and actual shrinkage data in the
tangential and radial directions.
(Refer to the Numerical Values window).
-
- Natural Durability
- The heartwood is
reported to naturally resistant to decay, attack by
termites and most xylophagous beetles, but logs are
reported to require prompt removal from the forest
and some form of protection against attack by
insects.
-
- Resistance to
Impregnation
- The heartwood is
reported to be respond poorly to preservative
treatment, but the sapwood has good absorption
properties, with adequate retention.
-
- Gum Exudates
- The timber is
reported to contain, and sometimes exude gum.
-
- Veneering
Qualities
- Some logs are
reported to be mainly from Gabon, are highly figured
and are converted into attractive veneers for
decorative applications such as, panelling, inlay
work, high class furniture, and fancy turnery work.
-
- Blunting Effect
- The wood exerts
moderate to severe blunting effect on cutters.
-
- Cutting Resistance
- Bubinga is hard and
heavy, but it is reported to saw slowly but readily.
-
- Planing
- A reduced planing
angle of 15 degrees is recommended to prevent
irregular and interlocked grain from tearing or
picking up.
-
- Turning
- The stock is reported
to turn well, despite its hardness.
-
- Moulding
- The wood is reported
to mould well, but irregular and interlocked grain
may cause pick-up and tearing if cutting angles are
not reduced to 15 degrees.
-
- Boring
- Boring properties are
reported to be good.
-
- Routing &
Recessing
- The wood routs and
recesses generally well.
-
- Mortising
- The material is
reported to respond well to mortising operations.
-
- Carving
- Carving properties
are reported to be generally good.
-
- Gluing
- Gluing qualities are
reported to be rather poor because of gum pockets.
-
- Nailing
- The timber is
reported to take require pre-boring in nailing
operations.
-
- Screwing
- Pre-boring required
before screwing.
-
- Sanding
- The wood is reported
to sand well.
-
- Polishing
- The wood is reported
to take an excellent polish.
-
- Staining
- The material is
reported to stain easily.
-
- Varnishing
- The timber is
reported to varnish satisfactorily.
-
- Response to Hand
Tools
- Generally works well
with hand tools.
-
- Comments
- Four fairly
well known species, all native to Africa, are
reported to be represented by the genus Guibourtia.
The species are reported to be botanically
similar but are very different in color. The most
plentiful is Bubinga, produced by G. tessmannii ,
and G. pellegriniana . The rest are Benge or Mutenye
which is produced by G. arnoldiana ,
Ovangkol or Ehie from G. ehie , and Rhodesian
copalwood from G. coleosperma , which is reported to
be less plentiful in international trade.
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