Working with Solid Ebony

Tips on how best to handle this scarce and costly wood. November 10, 2006

Question
We have been asked to make a cabinet in solid ebony. Does anyone have any experience working in the solid? I have been warned that it blunts blades and is hard to glue. We do have tungsten tipped planer blades. As it costs the earth, we are very keen not to make any errors. Thanks in advance.

Forum Responses
(Cabinetmaking Forum)
From contributor D:
I'll assume it is a small cabinet, considering not only material costs, but size availability. Ebony is not particularly hard on HSS knives or carbide saws. It hand planes, carves and scrapes exceptionally well. Keep in mind it has been worked with hand tools for over 3500 years.



From the original questioner:
Thanks. We bought some 4" x 2" solid in 7 foot lengths and it is all stickered up in the workshop to let it acclimatize. I think they were cut for walking stick manufacture. I'd like to know how much expansion and contraction goes on in Macassar ebony. Not much, I would think, being so tight grained. If the cabinet splits, we can't just pop out and buy some more.


From contributor G:
Diospyros celebica
Macassar ebony

Strengths:
o Distinctive grain pattern
o Very hard and heavy
o Very stable once dry

Weaknesses:
o Dust can irritate
o Slow and difficult to season
o Risk of checks and splits

Exotic, expensive, decorative wood:
Grown on the Indonesian island of Sulawesi (formerly known as Celebes), this is one of the rarest and most expensive woods you can buy. It is distinguished by the stripy grain pattern, which is largely dark brown or black but interspersed with much paler bands. The scarcity of the lumber is not helped by the tree's relatively small size.

Key characteristics:
Type: Tropical hardwood
Other names: D. ebenum, D. macassar, Indian ebony, coromandel (U.K.), Sri Lankan ebony
Similar species: African ebony (D. crassiflora), Indian ebony (D. tomentosa and D. melanoxylon), Andaman ebony (D. marmorata)
Sources: Sulawesi, Indonesia
Color: Stripes of dark brown and black, with lighter yellow or beige bands
Texture: Fine to medium and even
Grain: Generally straight, but there may be some interlocking or wavy grain.
Hardness: Very dense and hard
Weight: Very heavy (68 Ib./cu. ft.) (1090 kg/cu. m)
Strength: Generally used for decoration, not because the heart can be brittle but because it is so expensive.
Seasoning and stability: Very slow to season; the tree is often ringbarked (girdled) for two years before felling to start the drying process. Liable to split if dried too quickly. Very stable once seasoned.
Wastage: Low
Range of board widths: May well be limited
Range of board thicknesses: May well be limited
Durability: Very durable against rot, but some risk of insect attack

In the workshop:
Because of its cost and scarcity, this is not a lumber to experiment with. It is very hard, but is not considered to dull edges too badly. The dust is reported to irritate some people's skin.
Milling: You may need to reduce the angle on the edge of blades, and there is a risk of tearing when surfacing.
Shaping: Takes a good edge for profiling.
Assembly: Screws and nails will need pre-drilling, but the lumber glues well.
Finishing: Finishes to an incredibly smooth, high luster.

Variations:
Macassar ebony is often cut for veneer, but there is not much difference between plain-sawn and quarter sawn faces.

Sustainability:
Supposedly felled only by quota, but it has been listed as vulnerable. Certified lumber is unlikely to be available. There are few alternatives.

Availability and cost:
Not widely available, and very expensive.
Key uses: Interior, Cabinetmaking, Decorative, Ornamental turning, Inlay



From contributor P:
My experience is that Macassar ebony is quite stable when properly dried. The key is in the sawing and drying. You do not have much control over how the tree was felled and sawed, but you can assist in the drying stage. Overall, I found Macassar to be much easier to work than Gabon. I have always used G2 epoxy to glue it, but many others have had great success with Titebond.


From contributor D:
Solid should be fine, but if you are aware of J Krenov's work - as well as many others - then you know about exploding a board into matched faces and panels for more flexibility and freedom of design, as well as added stability.


From contributor E:
Ebony mills and sands easily. The tough part is finding cracks and matching the lumber well enough for a panel glue-up. You rarely see anything larger than 7ft 2X5-6in. My old supplier used to tell me that's as big as the elephants want to carry through the forest (might be true for the past, but I don't know how they do it now). I typically yield 55-65 percent of the purchased lumber. Wear a mask, the dust will get you. It hangs in the air for a long time.


From contributor W:
I have always used epoxy and have never found very large boards, either. Try to use the wood wisely; it's a limited resource. Resaw as much as possible for similar faces, a stable core is better than solid thick lumber. Your coefficient of expansion is more consistent and predictable.