12 June 2009

Tectona grandis

Hands in the air...I cheated and lifted this of t'internet.

"Latin name "Tectona Grandis Linn". Teak wood or Golden Teak is the king of hardwoods and it's one of the world's most valuable timbers, recognized for its durability and stability. Teak is more durable than any other hardwood and has unparalleled rich beauty. Teak can withstand all types of weather. Ancient Burmese and Thai royalty considered teak to be a royal tree. It has been the pillar of the shipbuilding industry for centuries. The decks of the Titanic were covered in Teak, and the wood is as good today as the day she sank on 1912. Teak is also used in the Middle East oil industry as one of the very few timbers that can withstand the punishing heat of the desert and will not readily catch fire. Teak can withstand harsh chemicals, and is resistant to fungi, rot and termites. Unlike other woods, teak does not turn black when in contact with metals. It looks best when applied transparent and light colors. Teak is the common name for "Tectona grandis", a large deciduous tree of the family Verbenaceae, or its wood, one of the most valuable timbers. Teak has been widely used in India for more than 2,000 years. The name teak is from the Malayan word tekka. The tree has a straight, but often buttressed, stem (i.e., thickened at the base), a spreading crown, and four-sided branch lets with large quadrangular pith. The leaves are opposite or sometimes whorled in young specimens, about 0.5 meter (1.5 feet) long and 23 centimeters (9 inches) wide. In shape they resemble those of the tobacco plant, but their substance is hard and the surface rough. The branches terminate in many small white flowers in large, erect, cross-branched panicles. The fruit is a drupe (fleshy, with a stony seed), two-thirds of an inch in diameter. The bark of the stem is about 1.3 cm thick, gray or brownish gray, the sapwood white; the unseasoned heartwood has a pleasant and strong aromatic fragrance and a beautiful golden-yellow colour, which on seasoning darkens into brown, mottled with darker streaks. The timber retains its aromatic fragrance to a great age. Native to India, Burma, and Thailand, the tree grows as far north as about the 25th parallel in these areas and to the 32nd parallel in the Punjab. The tree is not found near the coast; the most valuable forests are on low hills up to about 3,000 feet. Stands are also found in the Philippines and in Java and elsewhere in the Malay Archipelago. Teak is also planted in Africa and Central America. During the dry season the tree is leafless; in hot localities the leaves fall in January, but in moist places the tree remains green until March. At the end of the dry season, when the first monsoon rains fall, the new foliage emerges. Although the tree flowers freely, few seeds are produced because many of the flowers are sterile. The forest fires of the dry season after the seeds have ripened and have partly fallen, impede the spread of the tree by self-sown seed. Teak trees on good soil have attained an average height of 18 m in 15 years, with a girth, breast high, of 0.5 m. In the natural forests teak timber with a girth of about 2 m (diameter of 0.6 m) is never less than 100 and often more than 200 years old. Mature trees are usually not more than 150 ft high. Due to the oil and rubber found naturally in the wood, teak has a greater ability to withstand the elements than any other wood. For this reason it has been the preferred choice for boats, and in fact, it has been used on aircraft carrier decks! This is because of its ability to resist splintering, warping and rotting. (If left un-oiled, our furniture will turn a soft dove gray when allowed to remain outdoors. This process will take approximately one year.) Teak timber is valued in warm countries principally for its extraordinary durability. The timber is practically imperishable under cover. Teak wood is well known since early/ancient times as a valuable resource due to its long life reliability and weather resistance as well as its workable qualities. Pieces of teak have been found (in India) over 200 years old and still intact. Teak wood is used for shipbuilding, fine furniture, door and window frames, wharves, bridges, cooling-tower louvers, flooring, paneling, railway cars, and Venetian blinds. An important property of teak is its extremely good dimensional stability. It is strong, of medium weight, and of average hardness. Termites eat the sapwood but rarely attack the heartwood; it is not, however, completely resistant to marine borers. Teak also refers specifically to the wood and its characteristic color, which ranges from olive to yellowish gray or moderate brown. Teak furniture dates back prior to the 19th century used mainly by the Chinese for export to Europe. The Victorian era also incorporated the use of teak wood during the mechanical era of the 1840's with the invention of presses, veneer cutters etc which enabled them to create decorative elegant high class furniture. Another factor here is transportation (shipping) was also becoming more advanced. Burma produces most of the world's supply, India, Thailand, Indonesia, and Sri Lanka (Ceylon) ranking next in production."

Couple of things that the article fails to mention, first and foremost it's also been used for the decks of this ship...and I have a laser engraved lump of it! Second and foremost, it has to be the best neanderthal material ever, 'cos unless your planer blades are tct tipped (and all other edged blades for that matter) be prepared to spend a long time at the sharpening bench if you start a project in this stuff, as I did last night, when I cut the legs and rails for the new table.

It's a really fabulous timber, it just needs an inordinate amount of effort to use it, that's all...


Mitchell said...

Here in Canada, rough teak stock sells for up to $38.00 a board foot or approximately 20 British Pounds (sorry, no pound character) or $33 U.S.D.

While that, in itself, is seriously expensive, having laid teak decks on a 40' boat along with cockpit covering boards, I found that the cost of the stock is not the final price. By the time you add in the cost of damaged saw blades and replacement blades for scrapers, not to mention factoring in the cost of loosing an inch or two off of every chisel and plane blade you touched to the damned stuff, it works out to more like $43.00 a board foot.

I spent a fortune and laboured for an entire summer installing those decks. Once done, I baby them for three years, patiently waiting for them to turn the beautiful purple-silver I had seen so often in the tropics. It didn't happen. With our pollution and weaker sun, they turned a disgusting shade of bluish-black.

It took another two weeks and another few hundred dollars in scrapers and sandpaper to scape away yet another four or five hundred dollars of teak, this time in the form of dust, to get the decks back to the wood's true colour.

Once back to square one, I then made my third mistake - I oiled them. To do this properly, you lay on a coat of tung-oil and once the wood is saturated, you start to sand, and sand, and sand. The first coat is sanded with 400 grit wet/dry paper and with each consecutive coat, you move up the grit scale finally finishing the sixth or seventh coat of tung-oil with 1000 grit. The idea is to add sawdust to the oil to make a paste and then use that paste to fill the grain of the wood. After days of work, I finally achieved the most beautiful deck I had ever seen. The teak displayed a surface that was 12 inches deep, it had a sheen like polished marble and a surface that was like velvet. With the dark oiled teak and the black caulked joints (they are what kept the decks from being slippery), it truly was a magnificent sight.

That lasted two weeks.

Acid rain, the sun and other elements washed it all away. To maintain them properly, I would have had to add refresher coats weekly. All that work and expense lost because I didn't believe what the books said.

After a summer, the elements had eaten and washed away every trace of oil and following summer I coated them with a product called "Cetol", an oil derivative. It was the only thing that would stay on the wood for longer than a month. My beautiful $10,000.00 teak deck was a sea of yellowish-orange which I hated until the day I sold the boat.

Sorry for the long-winded comment but whenever I hear or read the word "teak" now, I tend to loose my self-control.



Woodbloke said...

Mitchell - really sorry to hear about the woes of your teak deck...sounds like you had a awful experience with the stuff. I've only ever used it for indoor furniture work which I guess is a totally different 'kettle of worms' to a harsh marine application such as a boat deck - Rob