Ghana's hardwoods: Gonclusion

fl NE of the most popular exports V not onlv in Ghana but in all of West Africa is afrormosi a (Pericopsis elata). Yellow to warm brown, its pattern ranges from straight grain to some mottle, resembling teak. Perfect for wall paneling, furniture and decks, its use is limited by its high price tag.

Sapele (Entandrophragma cylindricum) has long been another of Ghana's most popular exports. Dark red-brown in color, it features a stripe and bee's wing pattern and considerable variation in the grain. lt works fairly well with hand and machine tools, though tougher, harder and heavier than African mahogany. Readily available, sapele is used as veneer for furniture. cabinet work and interior decoration.

Resembling rich, red-brown sapele, yet somewhat deeper in color and without sapele's cedar-like scent is utile (Dawe sprague). The very large trees are of medium hardness and weight, with medium texture and superior strength. Durability is moderate since the sapwood is liable to attack by powder-post beetles.

The timber works fairly easily, although it may chip in planing and char in boring. lts uses are also like sapele's, but it is less suitable for decorative work and is valuable as a rotary-cut utility plywood. lt is mainly designed for interior furniture, ships' interiors, door frames, interior joinery and fittings.

Makore (Tieghmella hackelli), like utile, is one of the largest trees of the forest, rising up to 200 ft. high and reaching widths of 30 ft. The clear bole may reach 100 ft., though it is peculiarly prone to be completely shattered or badly split in felling. Colors vary from pale pinkish-brown to a rich red-brown. The wood is moderately hard and of medium weight and strength.

Makore is one of the most durable of local timbers. lt saws with some difficulty, but cuts cleanly and logs are markedly free from defects. And it works easily, despite rapid blunting of cutting edges. The wood screws and glues well, but tends to split in nailing. It is used for general construction, furniture, cabinet work, decorative panels and veneers, exterior doors, turnery and flooring.

Story at a Glance

Ghana exports wide range of hardwoods.. each has individual strengths and weaknesses... current promotion may mean more recognition African mahogany is its best known export. ..

Another durable hardwood, resistant to decay, termites and marine borers, is opepe (Naulcea diderrichii). A forest tree growing up to 180 ft. in height and 16 ft. in girth, its wood is hard, medium heavy and exceptionally strong.

The timber works with moderate ease despite its hardness. lt takes screws well and glues well, but must be bored before nailing to avoid splitting. Best uses are for harbor work, such as piles, fenders and wallings, and other types of heavy structural construction.

Similar heavy duty structural building, like fenders, wallings, bridge building and decking, is also accomplished using ekki (Lophira alata).lt also grows up to 180 ft., being even harder and heavier, weighing between 59 and 69 lbs. per cu. ft. The wood has an interlocking grain, low luster, coarse and uneven texture.

The durable material is moderately difficult to work with hand tools but can be worked by machines with less trouble. Preboring is necessary in screwing and nailing but strong glue joints are readily produced.

Mansonia (Mansonia altissima) is also being shipped out in increasing quantities. The wood is often labeled African black walnut, but this title is misleading. While it is somewhat similar to walnut in darker varieties, featuring whitish sapwood and yellowish-brown to greyish and purplish-brown heartwood, its color varies considerably and it is not related to the walnut familY.

It is usually straight-grained, smooth and fine textured, harder than American walnut, but similar in strength and other categories. Its heartwood is decay-resistant, and it works easily, glues well and finishes excellently. lts uses include veneer, interior fittings, joinery and flooring.

Ghana has always had the wood. And now, with its active promotional efforts. its timber and wood products industry promises to become better known.

Illll(lll BRII|GES built with pressure treated wood cost less and take less time to install than bridges of other materials.Once they are installed, savings continue because pressure treated wood can withstand severe weather conditions. Their natural appearance compliments their surroundings in any situation.

Polyurethane in European Building

Building materials utilizing polyurethane structural foams are being used in an ever increasing number in the European building industry.

Applications include spiral staircases, handrails, utility windows, residential windows, drainage grilles for flat roofs, domelight frames, roof ventilators and skylight windows. Improvement in reaction injection molding (RIM) materials allied with advances in processing technology makes the new advances possible.

Dr. Ulrich Knipp of Bayer AG in West Germany, described the new technology and its applications in a presentation in Denver, Co., in April, citing Velux skylight windows as an example. Advantages of the polyurethane moldings, according to Dr. Knipp, include good thermal insulation, design freedom, light weight, long service life, stability and the ability to combine with other materials.