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.

And the topic is: WOOD!

You must understand wood to successfully make things out of it. I will present this 5-hour class at the Woodcraft in Walpole, MA (about 10 miles southwest of Boston) on Sunday, September 9, 2018 from 10:00AM – 3:30PM. You will be equipped with the practical knowledge to use wood intelligently to maximize the quality of your projects and avoid the pitfalls that lead to disappointment.

In the woodworking instruction sphere, there are very few classes available on understanding wood, and most of those are small parts of much more extensive general woodworking courses. This freestanding, concise class is a great way to get the know-how you need. The store has an excellent teaching facility.

Go to this link and scroll down to September 9 to get sign-up details.

Among the areas we’ll cover:

• From log to board: Come to really understand grain and figure. Learn to astutely use figure to enhance your projects, especially curved work.
• Wood movement: We’ll cover practical understanding and applications, so this issue won’t catch you by surprise or riddle you with doubts. Try out pinless and pin moisture meters.
• Understand and see what really happens with resawing.
• How to buy and store wood. Spend wisely. How to spot and avoid defects in boards.
• Bring: your sharpened plane, card scraper, handsaw, and chisel/knife to make shavings and sawdust as you sample the working properties of 20 species of wood.

And I promise, the learning will be fun!

Double-coated tape earns Shop Miracle status for its simplicity and problem-solving versatility.

I prefer SpecTape ST-555H 1″-wide (Woodcraft item #15D25). This is a tough cloth tape with strong adhesion, yet it removes cleanly. It has a stiff, smooth paper backing that is easy to remove. I have used other tapes with soft paper backings that were annoyingly difficult to remove.

Its top uses in my shop are:

• Template work on the router table
• Bandsawing legs with three-dimensional curves: For taping the waste back on to restore the layout lines, double-stick works much better than wrapping tape around the leg.
• Mock-up designs: Lightweight parts can be rearranged easily.
• Bandsawing curves in wide boards: Tape an extra squared board to the back of the work piece for stability.
• Holding small/odd-shaped work on the bench

Here’s an efficient way to work with this tape. While applying the piece of tape to the wood, fold up a tiny corner to create a little “ear” of separated backing. Rub your fingernail over the main area of the backing paper to seal down the tape. Then grab the ear to pull away the backing.

Clear packing tape

This works well as a glue barrier. For example, I wrap tape on the tops and upper sides of the wooden support strips used for gluing up panels. The forms and clamping blocks for bent lamination work also get covered.

Oh, and of course this is essential equipment for returning that tool you bought that didn’t turn out to be as cool as it looked in the online catalog, or that, nope . . . ya just don’t need.

Cloth friction tape (rightmost in the photo)

I wrap, hockey style, my coping and fret saw handles with Ace Hardware black Cloth Friction Tape to greatly improve my grip and reduce hand fatigue. I also flat wrap some clamp handles such as the outer handle on wooden hand screws.

This stuff is grippy without being too rough on your hands, as can be anti-slip tapes. It can leave a bit of black residue on your hands when new, but not significantly as the wrapping inevitably gets sprinkled with wood dust. It does not leave sticky residue on your hands.

[3M Cloth Friction Tape appears similar but I have not used it. 3M 1755 Temflex Friction Tape is different – it’s coated on both sides.]

Silicone “X-Treme Tape” (Rockler) (second from the right in the photo)

This interesting stuff stretches a lot and bonds to itself without adhesive. It is useful for some dust collection fittings where it makes a nice tight seal. However, it really only sticks well to itself, and therefore needs contour on both parts of the fitting that it can tightly conform into, and so create a mechanical lock.

Funny that tape is even used in the woodshop where we sweat over joints, glues, and fasteners to keep things together. Nonetheless, a variety of tapes serve all sorts of duties, and it pays to be familiar with the options. From among 3M‘s numerous tapes, here are the ones I have found useful, working from left to right in the photo.

The workhorse is the #2093EL blue painter’s tape, rated “medium adhesion, 14-day removal,” very similar to the original #2090 but with Edge Lock (EL), designed to give cleaner paint lines for painters. This is handy stuff – as a drill bit depth indicator, marking the floor locations of machines, reminding myself not to reset a gauge, and on and on. For shim purposes, it measures .004″ thick by my calipers. 1″ width is versatile.

Second from left, #2080EL “low-medium adhesion, 60-day removal” is smoother and thinner at .003″. I like this one better for taping off areas to protect them from glue squeeze-out. It’s not a big difference for our purposes from #2093. The EL tapes do seem to lay down to a neater edge.

The green tapes are interesting. The thinner green roll is Scotch #233+, which 3M renamed to #401+. It has significantly greater adhesion than the blue tapes, and it is stretchy. It was developed for heavier-duty use such as conforming and holding to auto body contours. For woodworkers, it makes a great light-duty clamp in situations where regular clamps are awkward to arrange, such as gluing edge trim or small miters, especially with CA glue. It is much better in this regard than the blue tapes.

However, the green #2060 (fourth from the left) is more widely available than #401+, and can be found in home centers in a variety of widths. #2060 is practically as good as #401+: adhesion and tensile strength are nearly identical, and at 8% elongation before breaking, it almost as stretchy as 401+, which has 10% stretch. Both remove cleanly.

The beige tape on the right is #2040 Solvent Resistant tape. I use this infrequently to mask off an area from a solvent-based finish.

Surprisingly, the tensile strength of all of these tapes is about the same, from 24-27 lbs./inch of width.

So, let’s simplify. I suggest go to the orange palace and get a 1″ roll of #2093EL for general use, and a roll of 1 1/2″ #2060 for stronger adhesion and clamping. I covered the background info and the other options in case you need them.

Next: other tapes including . . . the Shop Miracle.

Several round-number milestones for this blog have converged, so it is time once again to take stock. Heartwood will be 10 years old in a few weeks. I have authored 200,000 words of content (not including comments), the length of 3-4 typical non-fiction books, accompanied by more than 1000 original photographs. The stats counter tells me there have been nearly 4 million visits and 12 million page views since the blog’s inception. (That’s actual human traffic, not robots, spiders, crawlers, etc.)

As I have said all along, Heartwood is about real-deal woodworking “from the sawdust and shavings of my shop.” The primary reason I write is, quite simply, that I want to share with you the joy of woodworking – the “quiet joy,” in Krenov’s words. I want to help empower you to build things.

The great majority of the posts deal with technical matters of tools, techniques, wood, jigs, and shop fixtures, but there are also explorations into the bigger picture of why we work wood, and the meaning the craft holds for us. I do not waste readers’ time with stuff for which they did not likely visit, such as contentious politics or accounts of a leak in my car’s radiator. I have tried to keep the writing engaging, fluid, and respectful of my readers, for whom I am most grateful.

I admit to being frustrated with the dearth of comments. Please, say hello once in a while if you are even slightly inclined. The interaction generated by your comments and ideas is fun for all of us. I also enjoy the many woodworking questions that I receive from around the world. I want to help you work wood.

The golden age of interest-focused blogging has long past, largely due, I think, to the dominance of social media, photo posting sites, and the explosion in video content engendered by broadband Internet. There is plenty of useful content out there, particularly videos, but much of it is idle junk. In any case, I think there is still unique value in writing.

So, will all of that, where do I go from here with this blog? Well, for now I am continuing. I have lots more to say, but this takes considerable time and effort, and I certainly want to maintain quality. I’ve even thought of adding short videos, but who knows.

I’ll take it one month at a time.

Most all, thanks for reading!

Rob

Looking back at photos of my shop as it was 16 years ago (below), I was struck by the differences from now (above). For example, all of the major machines have been upgraded, and I had yet to install most of the shopmade workbench features that now seem essential. Just as interesting, however, is the persistence of effective shop systems. For example, my sharpening bench is essentially unchanged, even in its location alongside the workbench, despite the whole shop being in a different location.

Now to my advice: Let your shop evolve.

By all means, sure, take your best shot at the initial set up, using your resources of space, money, time, and knowledge. But don’t get seized with paralysis by analysis, especially from drooling over dream shops in magazines.

There is no dream shop. There’s your shop, and you need to set it up and start building things in it as soon as possible.

In time, it will become evident what works and what changes are needed, based on what you build, your style of working, and the available resources. At any time, it is impossible to think through every contingency. Better to get going, and let it evolve.

In this way, you will have something better than a dream shop. You will, with persistence and some luck, have a real shop – your shop – and it will be right for you because it will change with you.

My first “shop” after leaving the home of my youth, was a Workmate in a hallway, tools stored in cardboard boxes, and wood stored in a stairwell. Yet I built. Check out Fine Woodworking #237 (Tools and Shops, Winter 2014) for the layout of my humble shop many years later. Of course, however, some features have evolved since then. The photo here at the top is more recent.

We’re all, always, setting up shop – because we woodworkers love to build things.

Accuracy of what?

You square the blade to the table saw surface – the setup. Looks perfect; you swear it does. But the workpiece is what matters – the outcome. So you take some test cuts, only to be swearing again, this time in a different way.

What going on? Well, your thinking is right. It is best to work as directly as possible. Assessing the test cuts is closer to the actual goal, which is to make a square edge on a piece of wood so it will fulfill its role in the project. The squareness of the table saw blade is one step removed from that goal.

Another advantage of relying primarily on outcome is that sometimes the error assessment can be magnified. Testing a crosscut for square is an example. The error can be doubled by pairing two cut ends together, or quadrupled by crosscutting around a rectangle.

In theory, a good setup should yield a predictable outcome. As Yogi Berra said, “In theory there is no difference between theory and practice. In practice there is.” Gremlins lurk in the table saw example and in nearly all such matters in the shop. Sometimes decent accuracy can seem impossible to achieve.

The problem is simple (kinda): there are other factors that come into play. You’ve made assumptions. Sometimes these are difficult to measure or account for. For major shop machines and most small power tools, the gremlins can usually be traced to these three key factors:

• Table/surface flatness. There should be no dishing, no bumps, and no twist. Any defects should hopefully be where they do not matter.
• Fence flatness. Fences need to be straight, but also without twist.
• Arbor alignment and runout. The rotating part has to run true.

In the simple table saw example discussed above, perhaps you squared the blade from the left side, but rip cuts performed on the right side are a bit out of square. Check if the table is flat. As another example, imagine the error stacking that can result if jointer tables are twisted and/or bowed.

Looking at that list of three key factors, unfortunately, they are things that you cannot correct easily, if at all.  What’s the answer? Buy the best quality tools you can afford, and check them for good bones. That’s where cheap stuff usually falls short. Of course, other factors come into play but without these basics in order, it will be rough going. Do not be distracted by cute features that are added to make tools sell.

There’s one more issue. When trying to produce accuracy based on outcome assessment, it may be difficult to quantify the adjustments needed to alter that outcome. In other words, how much of a change in the setup will result in how much change in outcome? This happens a lot with the bandsaw. Sometimes trial and error is the best you can do. Sometimes it’s best to make the setup as good as you can and just go with that. An example would be making the table saw slot parallel with the blade.

The main points are:

• Recognize the difference between setup accuracy and outcome accuracy.
• Be cognizant of the multiple factors that may affect outcome accuracy.
• Be aware of the common culprits.

Remember too, you’re going for excellence, not perfection.

What is the most likely pitfall to cause your next woodworking project to fall short of your hopes? Answer: injudicious choice of wood.

OK, sorry, I’ll state it positively: each project has the potential to be greatly elevated by smart choices in choosing and using wood. But let’s look more closely at this matter.

On the one hand, there is knowledge of wood in general. This includes things like wood movement, strength properties, and grain. As you design a piece, you choose species of wood, and then, much as an engineer, use that knowledge to work out the details.

However, wood is not clay, steel, or plastic. Each board is the product of the incredible diversification of the biological world. For this reason, to be really successful at using wood, you must be intimately familiar with the species of wood that you are using. Go beyond your designer and engineer mentalities to that of a biologist.

For any species, there is so much to be cognizant of when choosing the specific boards and deciding how to make the best use of them. Where was the tree grown? How was the log sawn? Were the boards air-dried or kiln-dried; were they steamed? How does this affect the working properties and color? What defects is this species prone to? How will the color change over time? And on and on.

Let’s take cherry as an example, but the important point is that every species has its own large set of potentials and quirks. Cherry’s generally wide availability and easygoing workability can lull you into complacency.

Of course, cherry darkens with time and exposure to light to produce that legendary brownish, brick red color, but this is accompanied by a varying amount of softening of the original figure. Some people like this, others may be disappointed. Some boards have more distinctly etched figure, sometimes with a greenish tinge, and seem to retain it better. Speaking of figure, I find the quartered surface of most cherry to be somewhat disappointing.

More vexing is cherry’s tendency to produce a blotchy effect with some finishes, especially oil. If a board has the tendency to blotch, it is virtually impossible to fully avoid, but it varies widely among boards, so, again, the key point is to recognize this and choose wisely.

Gum streaks are a defect to the eyes of some woodworkers, others may like a few. I’ve also encountered some cherry boards that have fairly heavy gum streaks along with an unappealing “dirty” look that is hard to detect in the roughsawn state. As for the lighter sapwood, some reject it entirely (accepting only “all red”) but some may like the effect, such as with live-edge boards. Cherry from northwestern Pennsylvania is said to be the best available.

When choosing curly cherry, it is a mistake to suppose that it is similar to curly maple. Curly cherry is essentially very blotchy cherry in a nice pattern. Thus, cherry that is sold as “curly” but contains only minimal curl looks poor, and you’ll pay more for it. I’ve also found that curly cherry that is sanded or scraped never looks quite as good as when it is handplaned to the final finish (and that can be tricky pull off), even when a film finish is applied. Curly cherry is quite a different matter than curly hard or big-leaf maple.

I could go on. It sounds like choosing players for a baseball team – good batting average but can’t hit left-handers . . .

I enjoy using a lot of different species of wood, and I’ve paid the price, literally and figuratively, for sometimes falling short in this area. On the other hand, knowing wood really well is a joyful and fulfilling part of the craft, well worth deeply exploring.

Have you listened to your woodwork lately?

We are all cognizant of the visual beauty of wood, its tactile warmth and texture, and the memorable scents produced while working at least some species. But here is a reminder to tune in to the sweet sound of wood.

Notice the resonance when closing a lid or drawer made of solid wood. Or the sound of a ceramic bowl placed on a solid wood table. Compare those to the discomforting clamor of melamine-coated particleboard. The sound of real wood just seems like the ease and contentment of home.

Our lives are filled with the cacophony of sheet metal, glass, plastic, and concrete. How welcome is the comforting sound of solid wood.

We woodworkers create in a very special material.

I recall even early in my youth intuitively sensing that there was something special about wood, and some of that came through its sounds. I remember particularly a sturdy solid wood truck in the kindergarten room and the sounds of loading it with solid wood blocks. That rig had a dignity unmatched by plastic stuff.

Of course, the sound produced from wood reaches its full potential in musical instruments. Remarkably, even with all the advances in materials science, the best acoustic strings and woodwinds are still made from wood. And some of that acoustic magic is present in the solid wood furniture and household objects that we make.

Take notice and enjoy!

Available now is a new and bountiful collection of images of James Krenov’s work through many years, commentary on some of the pieces, videos, and other interesting materials.

The Krenov Archive is an important component of The Krenov Foundation’s mission to continue the legacy of James Krenov, his values, approaches to woodworking, and teaching. It is largely the work of David Welter, co-founder of The Krenov Foundation and a staff member at Krenov’s school for many years, Dave Matthews, Krenov’s son-in-law, and Kevin Shea. The archive will grow significantly beyond the rollout, so stay tuned.

Those familiar with the master’s work can better appreciate its breadth and further their insight by exploring the archive. I know Krenov’s books exhaustively, yet I’ve found plenty of valuable and interesting material to study in the archive. I particularly enjoy seeing the drawings and construction process photos. Those woodworkers and anyone who appreciates the craft who are new to all that is JK will also undoubtedly find this resource exciting and enriching.

Please consider supporting the Krenov Foundation. Read here on Heartwood for one easy way that I’d bet just about any woodworker can do! Your help will directly support and encourage young woodworkers in their journey in the craft we love. Ultimately, the fruition of their efforts will give more people the opportunity to experience the “quiet joy” of work “from wakened hands.” And that, dear readers of Heartwood, is a very good thing in a too noisy world.

Thank you,

Rob