Fasten your seatbelt as we ride through the world of mahogany! Our tour will be mostly about woods that are similar to mahogany, and sometimes referred to as “substitutes” for it, but are better considered on their own merits.

We start our journey with “genuine mahogany,” aka Swietenia macrophylla, big-leaf mahogany, Honduran mahogany, Central/South American mahogany, or if you want to live and buy dangerously, just call it “mahogany.” Just the name sounds, you know, classy. People, including people who buy furniture (such as you might build) but know nothing about wood, are almost always impressed by “mahogany.”

Note that in the rear-view mirror is Swietenia mahogani, aka Cuban mahogany, the best of them all, once used for building ships and furniture, but long since essentially unavailable. You might find a bit of it for sale that was rescued from the occasional tree downed in a storm in south Florida, and there is a plantation operation on a South Pacific island. I once read that it works like “cold butter,” and having had a tiny piece of the stuff some years ago, I can confirm that description.

But back to S. macrophylla. When it’s good, it has a lot going for it. Boards with good density and color are a pleasure to use in your projects. It usually planes easily on the flatsawn surface, while the quartersawn surface often exhibits attractive “ribbon-stripe” figure due to interlocked grain. This is difficult to plane but quite manageable with scraping and sanding. The wood is soft enough to saw and chisel easily but firm enough to hold detail.

The stability of mahogany is legendary. Radial shrinkage is 2.9%, tangential 4.3%, yielding an excellent T/R of 1.5, and paltry volumetric shrinkage of 7.5%.

Then there’s the chatoyance – that wonderful shimmery gleam, lovely but not overpowering – that mahogany does so well. You know, classy. A shellac and wax finish looks great.

Unfortunately, big-leaf mahogany is a big pain in the neck. Why? First, because it is expensive. I cannot find even the drabbest mahogany for less than $10 per board foot. Yet it is extremely variable in quality. Some boards in the bin will have that nice density and color, while others are junk wood – light in color and density, or often with defects. In fact, I suggest avoid buying mahogany in the rough; look for S2S or hit-or-miss planed stock.

In the photo at top, all three boards are genuine mahogany. Yup, the real thing. The top one resembles sapele (more on that in an upcoming post), the middle board is what I consider nice flatsawn mahog, and the bottom one is genuinely trash wood, as far as I’m concerned.

The most notorious defects are compression failures, sometimes called “windshakes.” These are jagged cracks across the grain, usually through the full thickness but not the full width of the board. The fibers are broken, rendering that part of the wood useless. It occurs in the tree from severe wind forces, snow loads, or, what I suspect is mostly the case with mahogany, when the tree is felled. Beware: this defect is very difficult to notice in rough boards, where it lurks to disappoint you when you bring the wood home and plane it.

See the defect in the board below? No? Neither did I before I took it home.

Here is the other side of the board, with the compression failure clearly visible after I skimmed it on the jointer. The defect goes through the full thickness of the board.

S. macrophylla is listed in CITES Appendix II, and on the IUCN Red List as Vulnerable. We are probably encountering mostly plantation grown wood, and the quality is uneven at best.

And so, regrettably, mahogany is nearly off my list of good options for wood. Next, we’ll look at a common alternative, Khaya, aka African mahogany. There’s that word again.