the Carpentry Way: Dark Chocolate and Sponge Cake (1)                                                          

Dark Chocolate and Sponge Cake (1)

    
Following on from a recent post about acquiring some mahogany, Swietenia mahagoni, originally from Florida, I had a few additional observations I'd like to share in regards to this special mahogany, based both on some recent readings and my impressions from having milled up a bunch of this stock now. I've learned much in the past few days. We're all doomed, basically.

While I was searching for info on Swietenia mahagoni, I came across a British timber merchant who lists Cuban Mahogany as one of his species. On their page for the wood, one finds the following mouth-watering description:

"This stock is a fantastic find, unused old stock from a factory workshop originally imported from Jamaica in 1908. It is very rare, very famous and very desirable.

Then when you check their catalog for what is actually listed for Cuban Mahogany, you find out that this 'fabulous' and "very desirable" find is a few 2"x2" sticks, 24" long.  Twigs, basically. Uh, jeez, erection lost.

Keim lumber lists a few bards from a non-straight tree, and a few of those individual boards go for more than $10,000/ea.  nearly $20,000(!) Will anyone bite at that price? It won't be me. I think that is one of the most expensive pieces of wood I've ever come across. Kinda nuts.

From what I understand the wood I have is from a Florida Key, or nearby, harvested some 40 years ago. According to the writer Clayton D. Mell, the Floridian variety was the densest of all the mahoganies found around the Caribbean and down into south America. My direct experience confirms how heavy this particular material is in the hand.

However, just because a mahogany tree grew in Florida there is no guarantee that the hard and dense quality of native Swietenia mahogani wood will be what lays within.

A Proceeding from the Florida Horticultural society by Julia F. Morton entitled "Our Misunderstood Mahogany and its Problems" was an enlightening read in this regard. It seems that Florida, in line with its national reputation as a super site for invasive non-native flora and fauna of all kinds, has become a place where mahoganies of all kinds are being planted as specimen trees. You can find Swietenia mahagani, and Big Leaf Mahogany (S. macrophylla) planted, as well as Khaya spp., or African Mahogany. So, if you stumble across mahogany lumber purportedly from Florida, it doesn't mean it is the native kind. That's one point.

And in cases where the native variety has been planted for landscaping purposes, the nature of the environs strongly determines what the wood is like. Location is everything.

As Morton notes in her piece,

"It develops a tall, straight trunk and hard, dark wood in hammocks on outcroppings of limestone on the Upper Keys. If close to the shore, it is protected by a fringe of mangroves. On the more humid mainland and poorly drained soil, the wood is pale and not as hard; limb breakage is common."
Further the author notes, as regards the native mahogany,

"Its native habitat in southern Florida was picturesquely portrayed by John Gifford in his book Living by the Land:
"It is common ... in very low, limestone swamps close to the sea, where it produces wood of exceptional quality. It grows in little groups, often surrounded by red mangroves, and although spots where it grows are a trifle above the surrounding land, it thrives within a few feet of very salt water, flooded at times by storm and often actually sprinkled with salt spray . . . This tree is native to the Madeira Hammock . . . close to the Bay of Florida. Trees which have been there for a long time have on many occasions been flooded with salt water to a depth of several feet, and the land is more or less salty at all times, except when leached by heavy downpours of rain ... It grows in the midst of the mangrove swamps, on jagged coral rock so rough and full of potholes that walking there is difficult and even dangerous."

The note about the Madeira Hammock - the S. mahagoni is also termed 'Madeira wood' (Madeira stems from 'madera', meaning wood in Spanish.) - this location is found at the southern tip of the Everglades, West of Miami and north of the Keys - note the mark on the following map:




So that's the sort of ecology within which the good native mahogany can be found - not that there is much native Florida mahogany to be had these days except in exceptional/illegal circumstances.

I had never come across the term 'hammock' before as a ecological feature, so in case you are interested, here is the meaning according to Wikipedia:

"Hammock is a term used in the southeastern United States for stands of trees, usually hardwood, that form an ecological island in a contrasting ecosystem. Hammocks grow on elevated areas, often just a few inches high, surrounded by wetlands that are too wet to support them. The term hammock is also applied to stands of hardwood trees growing on slopes between wetlands and drier uplands supporting a mixed or coniferous forest. Types of hammocks found in the United States include tropical hardwood hammocks, temperate hardwood hammocks, and maritime or coastal hammocks."
As far as the ecology of the Tropical Hardwood Hammocks found primarily in Miami-Dade County, a very informative read can be found here. These hammocks are quite vulnerable to the effects of both climate change and associated changes in sea level, falling water tables, and human introduction of exotic plant species:

"Recent GIS mapping of invasive exotics throughout the Florida Keys shows that approximately 2,833 hectares (7,000 acres) of susceptible upland habitat have been invaded by exotic plants, especially Australian pine, Brazilian pepper and latherleaf (Kruer et al. 1998). Areas of disturbed substrate within and adjoining Keys hardwood hammocks are often heavily infested with exotic plants that are rapidly spreading into and displacing the natural plant community...Hybrids between native and exotic plant species have also begun to appear (Hammer 1996, Sanders 1987), ultimately threatening native species with extirpation or extinction."

Fortunately, most tropical hardwood hammocks outside of the Florida Keys along the coast of the Everglades are now protected from development, but climate change affects everywhere, and invasives are spreading without regard to lines that were drawn on a map, so it all remains threatened regardless.

Swietenia mahagoni coming from southern Florida is a wood in which the location in which it grew is a huge factor in the quality of the wood obtained. I imagine the same goes for the species when it is growing on other islands in the Caribbean. Take for example a quote from Patrick Browne (1756) in his work The civil and natural history of Jamaica, in regards to S. mahagoni growing in Jamaica:

"This tree grew formerly very common in Jamaica, and while it could be had in the low lands, and brought to market at an easy rate, furnished a very considerable branch of the exports. It thrives in most soils, and varies both its grain and texture with each; that which grows among the rocks is smaller, but very hard and weighty, of a close grain and beautifully shaded, while the product of the low and richer lands is observed to be more light and porous, of a paler colour and open grain . . . The most beautiful part of the wood is that obtained by sawing across the bottom of the stem and root."

I realize now that I am most fortunate to have stumbled into the 'good stuff'. Sobering to read the wood was but 'formerly' very common in 1756.

I mentioned in the last post that there is some S. mahagoni for sale on eBay, apparently 97 years old and originally from Jamaica. Here's a photo from one of the ads:



What's curious to me about what is pictured, if it really is S. mahagoni from Jamaica (which is one of the places where it does naturally grow), then is why is this wood so light colored? The material I have, though not as old as 97 years (since cutting), is dark purple, and I have found that the surface oxidation, after some 40 years, penetrates deeply into the wood. Even Big Leaf Mahogany turns a darker color after a few years, so, I'm a bit suspicious of what is advertised there on eBay. 97 years old - really? It's priced at $32/board foot. To give a charitable assessment, maybe it is a variety which is much blonder in color and doesn't oxidize darker as it ages? Hmmm, it's not convincing me, but you never know. I think I'll give it a pass, and in any case, when I contacted the seller for a list of his boards and their sizes they did not reply, so I doubt we'll be getting to the point where they would send samples.

As mentioned earlier, I have now milled up a bunch of the 'Madeira Wood'. Here, laying on the infeed table of the surfacer, are the components for the upper and lower horizontal frames with a few pieces of leftover stock standing to the left:


In the leftover pile I have a ribbon stripe board which is a bit of an orphan since it does not match anything else in this piece, along with a short and wide chunk which unfortunately has slash grain and is of limited usability:


More bug-eaten trimmings, and a pith board on the left:


Next are the pieces which will form the main posts, the front door frames, and some of the back framing of the cabinet:


While it is certainly true that to have the most direct feel for any wood you need to chisel it and plane it, or turn it on a wood lathe, I have nevertheless formed a strong impression of the material just by running it over my jointer, through my bandsaw, and even the planer. I can report that it does not suck. In fact, I am kinda ruined now for Honduran Mahogany. I was finding myself a bit giddy after cutting stock for a few hours. And I'm only giddy once every few years.

I now have a glimmer of understanding as to why joiners and furniture makers of the 18th and 19th centuries coveted this material like they did, and found the Big Leaf Mahogany 'spongey' by comparison.

If you would entertain an analogy, S. mahagoni, at least what I have, could be described in the following manner: while Honduran mahogany is some kind of Weight Watcher's™ diet chocolate bar, this stuff is more like a decadent fudge and dark chocolate bar. Or, put another way: Honduran Mahogany is like Wonderbread™, while Cuban Mahogany is like an artisanal loaf from a specialty bakery with a chewy crumb and intriguing flavors. It's hard to explain otherwise. I am in the process of obtaining more, as much as I can afford. Fortunately my sister in law has lent me some money to help out with this purchase, on very generous repayment terms.

I face a few challenges, beside staving off personal bankruptcy in my lust to buy more of this wood. One is the oxidation issue. The dark chocolate to purple color of the wood is the product of some 40 years of exposure, and the oxidation has reached deep into the wood - close to 3/8" (1cm). That means that re-sawn sticks have reveals of much lighter wood in the middle, trending towards the dark brown as you reach either arris on the face.

Obviously, a year or two down the line, the freshly-cut surfaces will darken and begin a journey to a point where it will all look much the same, namely dark chocolate with purple tones. I'm sure that 5 years from now it will be a good portion of the way there. However, the 'brand new' appearance of a cabinet is important. I'm not one of those people obsessed with closely matching colors  - that's more of an interior designer tic it seems to me. I enjoy the variegation of natural materials, and like getting to know them as they change over time. However, the difference here between faces is quite striking, so maybe I'll have to do something.

I spoke with the fellow from whom I obtained the Cuban Mahogany. He has long experience with Big Leaf mahogany, but has only worked a very small amount of his cuban stock, and was familiar with the issue of which I asked. He suggested a solution which had also crossed my mind, namely using dye on the lighter faces. He said that the dye will, over many years, weaken in effect, and sorta 'wear off' the surface, however as that happens the wood is naturally darkening, so it's like a simple case of replacement over time. That sounds good to me, and he recommended a particular Behlen's product, an alcohol-based non-grain raising dye in the Solarlux line, the Van Dyke Brown. I've found Behlen's stuff to be good, though for dyes I've employed TransTint products previously. I'll of course test this stuff on a small scrap piece first. I also plan to check in with my client to see how he might like the piece without the use of dye to obtain greater uniformity of color. If it were my piece of furniture I'd be inclined to use the wood 'as is' and let it age gracefully, but not everyone will feel similarly. I think I'll build the piece and see how it looks all assembled before making a decision in that regard.

This cabinet, as it is going into a bedroom and will not be exposed to the same sort of hazards and wear conditions as were the coffee table, side table, and sideboard I built for the client, could perhaps be fine with a thinner, less tough finish, something even closer to the wood. With that in mind, I've chosen a German product made by Kreidezeit, and sold in the US under the Unearthed Paints label. This is a 'hard wax oil', and is a blend of Carnauba wax, colophonium resin (that is, Rosin) and a Tung Oil/Linseed oil mix. The product is 100% solids, with no solvents or water. No friggin' VOCs to deal with, which is all good as far as I am concerned. I initially came across this wax oil product on a Japanese website, which lead me to find the German company site and check it out further. I was glad to find they had a supplier in the US.

I've heard good things about the 'hard wax oil' and it is very simple to apply, just wipe on, leave 20 minutes and then wipe off, and you are done. Mahogany, when planed, has a very pleasant feel, and I want to put the minimum sort of finish on there. I'm a bit tempted to go with the shiraki approach, just hand-planed and that's it. We'll see. Maybe, like the tsuitatte I built a few years back, I'll put finish on the main surfaces, and leave other sections planed only.

The other challenge coming up lays in dealing with re-sawing. I've designed this cabinet to have front doors and rear walls with panels 22" wide, and top/middle/floor panels around 27" wide. Obtaining these widths was no problem from the Honduran slab stock I had obtained, however the re-sawing cannot be tackled with my Hitachi re-saw, as it maxes out at a mere 15.8" (400mm) of cutting height.

Though I showed these in the previous post, it wouldn't hurt again to look at the panels for the front/back, and the drawer floors:


I have only made the two cross-cuts out of one of the slabs so far, mostly removing the ends with splits in the process, as I am proceeding with an abundance of caution. Look up 'trepidation' in the dictionary and you will see my forlorn visage.

As many readers will undoubtedly know, there are two standard ways to produce thin panels from thicker stock:

  1. joint/or machine a flat face and then plane it down
  2. re-saw
These boards are 5/4 thick (32mm), so the prospect of planing off 60% of the material to obtain a 1/2" panel, or 70% off to obtain a 0.375" thick panel, is a more than a little disheartening to consider. Planing down is, however, if not conservative of material, conservative in terms of obtaining a good outcome. It's reliable, but wasteful.

Re-sawing can be fraught with peril at times, and the more precious the wood, the greater the peril. If the boards have stresses in them, the process of re-sawing can cause these 'stress monsters' to suddenly leap into view, and at worst one can transform a 1.25" slab into a bunch of firewood with just one cut - though you can generally see what is happening well before the cut is done. If that were the outcome, then the irony is that taking a re-sawing approach, which seems the most parsimonious in prospect, could end up being the most wasteful approach.

Mahogany is quite stable in general, and my cross-cuts of the above chunks from the slab revealed little or no stresses, so I am less anxious about this potentiality. But it remains a risk, so I am only going to try the re-sawing on these few pieces of stock to start - in fact, I'll saw the smallest piece first and if things go awry I will likely jump to 'plan b' (i.e., planing down) for the rest.

There are two other troublesome factors with the re-sawing approach in this case, one already mentioned: the stuff is too big for my bandsaw. A little research revealed that I need a bandsaw with something like 40" wheels in order to re-saw 22" stock - never mind 27" stock - and feeding something that tall through a blade by physical effort alone would be chore and require the set up of a really tall fence. I don't know anybody with such a large re-saw, in fact my own re-saw is the largest in my building with three other wood shops, and has tackled everything I have thrown at it up to now. Buying a bigger bandsaw just because of this one challenge does not make sense, even if I had the money to throw at it.

I've also considered using a horizontal sawmill, but fixing the board in place is one issue and another is the fat kerf of those mill's blades, not to mention their coarser level of precision in general, all of which leads me away from that route. I did think about finding someone and asking them if I could mount a hardwood cutting blade for dry material into their mill, but I don't know anyone with a good horizontal mill anyhow.

I have concluded that ripping the stock by hand is the solution, preferably with Mt. Fuji in the background:


I'm moving shop and I'm shopping for period-correct Japanese clothing as I write this piece (surely you get that I'm joking?). I know you all would love to see me ripping some lumber in the equivalent of a g-string. Unfortunately, I can only do the top-knot effect these days with a wig. And it comes to mind: who needs a gym, when you can pit saw?

Wait a minute, you might say, why not rip the material into 14" wide stock, say, re-saw that on your machine, and then glue the pieces back together again? Why, nobody would ever notice the glue line! 

Yah, I've thought of that, and may make use of that approach, or something similar, for the less exposed panels, as are found on the floor and middle of this cabinet. but for the exposed panels on the front and top, I really want to stick with one piece panels. I know glues are the most wonderful thing ever invented, and god knows some woodworkers would just as well dispense with the wood altogether and just spend their time hugging and grinding plastic resin all day (or would they, hmmm?) - I know that modern glues are fast, convenient, easy to apply, and can be stronger than the wood itself. I guess I have a different ideal about what I want to make and how I want to make it and dammit I will be unreasonable and take the more difficult road with this phase of stock preparation. 


I will re-saw these by hand. It is unlikely to be 'fun'. The Ming Chinese cabinets of rosewood that I so admire had panels which were hand rip sawn, in a super hard difficult material no less, and they have stood the test of time. I have it easy by comparison with the "soft and spongey" Honduran Mahogany. Why, it should almost re-saw itself it is so spongey

I'm sure those guys (er, slaves?) in 16th century China didn't much enjoy the re-saw aspect of those projects, but the effort they made was definitely worth it in terms of outcome. Of course, the choice at the time to re-saw and not use glue was also driven by the fact that the weaker glues they had available could not be relied upon like our modern stuff - - and they were using a wood which is, to this day, still pretty tough to glue with any confidence. I get that. 

I'm going to get a large sticker made for the back window of my truck, saying "F*ck Glue and F*ck all of you that voted For Glue". Has no one thought of this before? Maybe not my style, and, in any case, I don't have a pickup truck with a large back window upon which I can post such an important message. It would get people's attention though....

The other factor is that, with a deep re-saw cut, blades can sometime wander in following grain and, worst case scenario, one or more of the panels you are resawing gets gouged by the saw beyond a point where it will yield a clean piece after being planed down.

Dude, use a laser! Didn't you cut those other joints with a laser?

Whattabout a Froe? You need to rive that material!

I've considered various options for re-sawing, and the time will come to make that bed and go and lay in it. Well, soon enough anyhow. I'm waiting on the production of a saw blade for a tool for that very end, as I'm going to try a French-style frame saw for this task. More on that as it happens, probably towards the end of December.

If the method I've come up with does not come out well, then I'll be using the 'plane down' method for the rest, which means a lot more of the slab stock will be consumed. I'm hoping that does not come to pass. 

Due to apprehensions about how much wide slab stock is at risk of being turned into chips in my dust collector, and due to the likelihood of wide slabs of mahogany being unobtanium in the coming years, I have gone ahead and purchased two more Honduran Mahogany slabs from Irion. One is the last of their 48" wide 5/4 slabs, while the other is a 5/4 x 30"-wide slab at 14' feet of length. My plan with the 14-footer is to chop off the end 4' and use that portion as the one-piece top panel of the cabinet. I'll plane that one down, accepting the lousy conversion from stock to finished piece. The 10' piece that remains will go into inventory. The 48" board is also for inventory.

For the cabinet floor and bottom panels, I have adopted a different strategy. I will trim some 14" wide quartersawn pieces from one or both sides of the slab(s), then re-saw those boards in half on my bandsaw, and dress them to dimension. Then I can put the two pieces together on edge to form 2-piece panels. I will not be gluing them though. One I will leave to float, using a t&g joint in the middle, while the other, the bottom panel, will have the boards mechanically connected to one another with a devious joinery method I have come up with.


Next post will deal with design issues for this piece. I hope you'll stay tuned, and thanks for visiting. Click on the link for Post 2.