Not all knowledge can be written down

Good news – the guitar top seems to be well glued to the sides, with not strange gaps or misalignments. The arch that was built into the top and sides seems to have retained its form – the lower bout tilts back from the plane of the upper bout and neck by a few millimeters at the bridge location. Pictures will appear in a future post.

Now that the top is being held within the frame of the sides, I can proceed to “voice” it by selectively removing material from both the top and the braces. In theory, there is a “sweet spot” of resonance where the sound board just feels more lively. The problem is, I’ve only read descriptions in print of what this might sound like. The few recordings I’ve come across just can’t do it justice through laptop speakers. It’s as much a felt quality as a heard quality. So I’m feeling really cautious at this stage, because if I remove too much material I’ll cross the threshold into “floppy,” where the soundboard loses its important acoustic properties altogether. (It will also likely fail catastrophically under the tension of the strings).

Right now it’s like I’m hiking in fog. I can set off in a particular direction, and I’ll have a sense of whether I’m climbing or descending, but I can’t backtrack. I’d like to climb to a local peak, but from this position I don’t even know which direction to set out in. Like I said, no backtracking if I set out in the wrong direction. And how to translate this metaphor of setting out in the fog to deciding which braces to lighten, where to sand down the top? I have no idea. I think I’ll end up just making some tentative, global changes, thinning the top overall by a few thousandths of an inch. One guidebook actually suggests making guitars in identical pairs – as you alter one soundboard you’ll still have a reference to judge against. Oh well, that’s not my case this go-around.

What I really need is to be guided by a master who can show me the sonic landscape of soundboard performance, what the boundary conditions are, and ways of getting to regions of that sweet spot (even within the region of “good resonance,” people may vary the qualities as a master of taste).  There is a builder up in Belmont I could try to hook up with for advice. (Actually, what have I got to lose for asking?) There are others who offer more formal classes and workshops in voicing the instrument.

It’s clear to me that this is one of those learning situations where patient guidance of a teacher is called for. I’ll still try to find what I can on the Internet – maybe somebody has done a really high-quality instructional video. But in the end it’s one person trying to convey a sense of things to another, and in that dialog understanding emerges.

I had a similar experience just last night – we went up to see a classical guitar concert by the Romeros (a dynastic family of musicians). They played as a quartet, and some of the members performed duets and solos as well. Celin Romero performed two Villa-Lobos preludes I’ve been working on (#1 and #3). HIs rendition of Prelude #1 in E minor was ear-opening. The manuscript notes supposedly say something to the effect that it represents two sides of Brazilian character, both a yearning melancholy as well as sense of verve and gusto. The form is A-B-A, where the opening A section (the “yearning” part) is repeated after the B (more exciting) section.

Celin took the first A section far more delicately than I play it, and more patiently than many recordings I’ve heard. He was measured with his phrasing, allowing the piece to really breathe. I have to say I was a little disappointed in his B section (but I suspect, based on some technical choices he made, his fingers may be showing their age), but overall I was glad to hear and SEE him play it first-hand. Again, all of the manuscript notes in the world would not convey what it could sound like, compared to hearing a live or recorded performance (I probably own at least 3 versions of this prelude on CD, all with a different emotional interpretation. Celin’s was the 4th I’ve heard from a professional).

So, I’m off to find some good acoustic guides to soundboard voicing, and I’m inspired to pick up the Villa-Lobos prelude again. 🙂  Til next time.


Oops I did it again

Every so often I find myself writing a variation on the same post – the idea that working with wood entails largely non-reversible operations. Essentially, woodworking has no “undo” command. I’ve written about that back in October here, in Feb 2011 here, Aug 2009 here… oh, there’s a post from June 2007 and one from June 2006, too. Eight years and counting of noting the same problem – rushing forward without stopping to think one or two steps ahead. The consequences of “just try it” are often irreversible.

A friend at work had a Spanish cedar platter that had once been her grandmothers. She packed it in a suitcase for a long flight and it cracked in transit. Fortunately it was a clean split and hadn’t completely separated into two pieces, so after looking at it I offered to glue it up. I wasn’t exactly sure what I would use for clamping pressure, but felt confident I could use a band clamp, a bunch of rubber bands, or if I had to, cut out clamping cauls on a bandsaw and use bar clamps. As it turns out, rubber bands did the trick. I flooded the joint with glue (in hindsight, I should have tried to be more economical and use a syringe that I’d forgotten I had) and clamped it up.

Yellow wood glue is a great adhesive. In a tight joint and with proper pressure, the adhesion will be strong than the wood itself. That is, if you try to re-break the platter, it will split somewhere other than on the glue line. It also cleans up with water, doesn’t smell, and isn’t carcinogenic. One problem, though, is that if you just try to smear it off the wood while still wet, it can leave an invisible coating on the wood that will show up as a blotch when you apply a finish. So the general rule is to let it cure for about 10 minutes and then carefully scrape it off as it gets “gummy.”  I’d flooded quite a bit on the joint (my first “mistake”) so I knew I’d be waiting more than 10 minutes to clean it up. Eventually, though, I did gently scrape most of it away.

Spanish cedar platter, glued

Spanish cedar platter, glued

Here’s where I rushed it – after an hour or so (when I knew the glue had set) I saw that one part of the repair was just every so slightly out of alignment. The halves were offset by maybe 5 thousandths of an inch, about the thickness of 2 sheets of paper. Not terribly visible, but I could still see it and more importantly feel the ridge as I ran my fingers over the joint. So then I did what I would normally do – I grabbed a small card scraper and started to scrape down the seam until the two sides were flush with one another.

Except… this platter was finished (varnish or shellac, I can’t quite tell yet, but I’m leaning toward shellac). Which means i put a nice scrape mark in the middle of a finished platter. Ugly! I hadn’t thought of the consequences of taking a scraper (or any abrasive) to the work – to do it right I’d probably have to strip off all the finish and re-finish the piece. Even that wasn’t such a problem, but this wasn’t my piece to play around with. Remember, it was my friend’s late grandmother’s. Now I’m feeling really badly that I might have made things worse. I’ll take it in and talk over options over the next day or two, once I figure out what the finish actually is (easy test – if I rub it with alcohol and it dissolves into the cloth, it’s shellac. Otherwise varnish). Please let it be shellac – it’s easier to play with (again, dissolves in alcohol) and I might be able to just fix that one area and give the whole platter one more good top coat or two to make it all look even.

I’m hopeful that I won’t be referring back to this posting six months from now, but history has a way of repeating itself.

“Look at me” vs “Look at that” social media

Day #2 of NaBloPoMo, reflecting on how various social media platforms are used. I once heard a radio commentator describe Pinterest as a “look at that” platform, whereas Facebook is a “look at me” platform.

I’m generally more comfortable writing and posting “look at that” sorts of entries: commentaries on current politics, pointers to interesting artistic sites, and the like. This blog, however, started as a reflection on my own creative processes and how my personal projects interest with my professional interests. Perhaps this is one reason why it’s been so hard to sustain; my personal revelations simply don’t come on a daily schedule, and I’m more reluctant to share the personal than the professional or external finds.

Some blogs are clearly in the “look at that” category. I’ve been following Curmudgucation lately (acerbic and insightful commentary on current trends in education “reform”), where the author manages to crank out at least one good post daily, sometimes more (it helps that he’s a professional English teacher, I suppose). There are more than enough issues in the world to sustain a daily “look at that” blog, but commentary on public affairs hasn’t (yet) been my motivation to write (I suspect this will change when I reach my “you damn kids get off my lawn” dotage, and feel entitled to tell the world how to run itself).

Greta Christina’s blog mixes the personal and political, and is stronger for that. Most of her writing is solidly in “look at that” territory, although she recently posted a series in which she documented her own descent into depression and the actions she took to pull out. But that was a “look at me” with the clear intent of helping others, using her own journey as “that” to be examined.

My own Facebook postings have largely been in the “look at that” category. I was reminded of this when I clicked a button to generate a word cloud of my year’s postings, and only three main words popped out. The app was pulling only my personal status updates, not my posted links to other articles/sites. Clearly I had not been posting many “look at me” status updates. And yet, one of the joys of Facebook is seeing the day to day status updates of friends far away; should I not be returning the favor? Perhaps “look at me” can be driven by needs other than ego gratification, a way of reaching out and touching others, giving back to those who provide those momentary smiles throughout the day.

I feel like every blog posting should have a “lesson learned” or neat little summary. In writing this I’ve come to see the “look at me” posting differently than when I first opened the post. That’s one of the benefits of writing, right? Our writing speaks back to us and leads our brain down paths we might not have found just sitting idly on a sofa lost ion thought. On a related note, I hope this daily exercise improves my non-technical writing fluency; I can see how my word-smithing has suffered for lack of practice.

(Oh, I’ve discovered the the cross-posts from WordPress to Facebook look better with a photo caption. Here, have a cat.)

Till next time,

Mastery and other paths

Once again, the commitment to write – something! – at least weekly is turning out to be an interesting challenge. Some weeks are rather “ordinary,” where there are no grand epiphanies to be written about. What to write on these ordinary weeks? I suppose look back on the ordinary moments and see what themes emerge.

Last Tuesday I went for a trail run (first one of the season). Near the trailhead is a site where the city tree trimmers drop off the logs and limbs from major trees they’ve taken down. Local scavengers (the 2-legged variety) come by to take home some free firewood, while others (like myself) look for wood to squirrel away in our shops.  On Tuesday there were a couple of folks there with a portable saw mill slicing up some nice redwood slabs.  I was limited to what I could physically lift and carry over to the trunk of my car (as well as what I could store in my garage/shop), so I walked away with a couple of pieces of oak, what looked like crotches and other gnarly pieces with severed limbs and knots sticking every which way out of it.  These can often hold beautiful gems of wood grain on the inside.

I split one piece in half, chucked it onto the lathe (without even rough-cutting it into a circle), and started turning away the outer bark. There were some inclusions (bark that had grown inward between the limbs that met in the crotch) that promised an interesting pattern. Of course, they were also structural weaknesses – would the bowl hold once I started hollowing and thinning the walls?  Well, as the pictures below show, it stayed together.

That was a good exercise over the course of a couple of evenings. Having free wood to play with allows me to experiment and take chances with design choices – I have nothing to lose but my time, and even that is in service of learning and improving. As it turns out I might have tweaked the profile of the final bowl just a little, but overall (so far) it looks like a serviceable bowl for serving nuts or snacks at a party.  Whether it survives the drying process (which could take several months) is another question. “Green” bowls distort upon drying, and the structural weaknesses in the wood could decide to give way.  That’s part of the delayed learning process.

So this project was a small learning segment on a much longer journey of mastery. In fact, that’s what most of the week was like: I learned a little bit more about some technical aspects of my day job, had some minor breakthroughs in my relationship, continued practicing music… just staying open and aware and letting the learning happen.

The late George Leonard wrote a book on “Mastery.”  A PDF copy can be found here at scribd. It’s a fun, easy read, and very insightful. A keen observer of human learning (his own and his Aikido students), he’s characterized some typical “paths” that we take as learners. His characterizations have what we in the biz call “face validity” – we recognize the truth in them intuitively.

First up, the path of mastery:

If you think of the vertical dimension as “progress” in a general sense, and the horizontal dimension as time, this is Leonard’s take on the master’s path. It involves lots of time spent on plateaus, simply practicing our practice. Then (although the detail isn’t apparent in this diagram, but I’ve heard him describe it this way), things start to fall apart – there’s a small dip before the growth spurt. Growth tends to happen in spurts, and then there’s a settling back down into another plateau. As they say on the bottle: lather, rinse, repeat. This is mastery.

There are a couple of critical components to this path. The first is that most time is spent making very little discernible progress. That can be very discouraging to people who like instant gratification or quick fixes. The second is the somewhat chaotic nature of the growth spurts. In particular, that sense of things actually getting worse before they start to really improve is paradoxical, but I believe it signifies the beginning of some significant cognitive/neurological/whatever reorganizations. A time of “things falling apart” is emphatically not the time to give up in the pursuit, but to hang in there just a little while longer – great learnings are just around the corner.

Leonard’s three other paths are pathological cases (no pun intended) of how we fall off the path of mastery.

The Dabler

The dabler’s path is to start something with enthusiasm, experience that first rapid growth spurt, but when the inevitable plateau comes around say to oneself “this is it? I’m bored… time to move on”.  Variations on this theme include “I guess I wasn’t cut out for this” or “I guess I have no talent.”  So we move onto different activities or fields, and experience the same dynamic…

The Obsessive

The obsessive dives in 110% to a new activity. S/he attempts to prolong that initial growth spurt through increasing effort, refusing to accept any form of the plateau. “If you’re not growing you’re dying” is the motto.  Ultimately this simply isn’t sustainable – nobody can keep improving at a constant pace forever (I claim that as if it’s a fact, but it’s just a generalization from personal observation. If anybody knows of a counter-example, please fill me in!).  In athletics we see the injury-prone athlete who doesn’t know how to recover or taper effort.

The Hacker

This one is my personal nemesis.  The hacker starts off looking a lot like the path of mastery. Growth spurts, plateaus, more growth spurts. But then there’s that plateau that never seems to end. What’s happening here is the appearance of steady practice, but not masterful practice. And although I cite this as my personal bugaboo, we all probably do all of these in various areas of our lives. I enjoy bicycling, but my mountain biking skills haven’t noticeably improved over the past decade. When I was training for a century I was on a good mastery path, but then ramped down the effort during the fall and winter. My history with music is one of very long plateaus, dropped interest, and then a long time spent regaining the facility I had when I last stopped.

(Well, I guess I found something to write about, even if it’s just reflecting on someone else’s writing)

I’d like to – obviously – stay on the path of mastery in as much of my life as possible. I’m doing it in my primary relationship – I’ve experienced more steady, genuine growth here than in any other time of my life, and have also never worked as diligently at it. I’m trying to stay attentive to my growth in woodworking and woodturning. The challenge for me at the moment (as has been the case in the past) is musical – staying at it when sometimes what I’m playing doesn’t flow very well.

Flow. Leonard cites Csikszentmihalyi’s work on Flow as being a characteristic state of one on the master’s path. In my day job as a researcher I experience flow frequently, getting lost in my work, not knowing where the time has gone.  That’s one place I don’t worry about falling off the master’s path. Similarly in the woodshop – I can stay at a task all day, plodding along at a relaxed pace, engrossed with what I’m doing.  I think the trick for me in music is to find the style and level that lets me flow. I’ve played mostly classical guitar, which is technically demanding and not always the most soul-satisfying genre of music. I’m been branching out more this past year, taking classes in celtic and folk music, trying to find that style that makes it effortless to pick up an instrument and practice on a daily basis.

So there – I found something to write after all.  I do recommend Leonard’s book (available on Amazon and probably still in print at brick-and-mortar stores) as a fun read, particularly for my friends in education. And of course, I’d love to hear your own stories of mastery (and/or other paths) in the comments section below.

Vanity and chasing after wind

Although I’ve committed to writing a blog entry every week, I usually have no idea what I want to write about until I sit down on Sunday evening. Tonight I ask myself “what have I learned this week?” – and several nuggets come to mind.

  • I was reminded – again – that I have to regulate my media diet. As I posted in an earlier blog about “right involvement,” there’s paying attention to bear witness, then there’s being consumed by the hysteria and hyperbole that passes for political discourse. I’m getting better at closing the browser window when I feel my blood pressure rise.
  • I was reminded that it’s possible to improve by being aware of one’s shortcomings, focusing on how to overcome them, and putting that learning into practice. There’s a bowl turning story here I’ll get to shortly.
  • After a week of not-very-inspiring work I learned that there are limits on how long I can go without some “juice” or passion in my work day.
  • I learned/remembered that the race is not always to the swift, not the battle to the strong.  The American Educational Research Association annual meeting is coming around, and so is ample opportunity to compare my professional life to those of friends and colleagues. I’m getting tired of my inner narratives that say I “fizzled,” or “didn’t live up to my potential” professionally. When I stop comparing, I’m happy with where I am and where I’m headed, and am resolved to use this year’s conference as an opportunity to reconnect with my interests and passions.

I worked on two projects this week that followed different trajectories. First, the bowl project. As I alluded to in my last blog post, I started over with a solid block of wood to keep my design constraints relatively free. Overall, this was a very successful strategy. I turned the outside profile of the bowl, actually finish sanded and oiled it, and turned my attention to hollowing out the inside.  Wham! the bowl (now a solid piece of wood) goes flying off the lathe, into the wall, and onto the concrete floor.  Bruised, but otherwise fine.  Re-mount it, start to hollow… and wham! off it goes again, this time splitting the spigot I was using to chuck it to the lathe.  Uh oh.  Clearly I’m doing something wrong.  So I re-glue the spigot and hit the books.

It turns out that, yes, my approach to hollowing was off in a couple of ways. First, I should have been making steep cuts starting near the center and pushing directly in toward the bottom. That is, I should have been taking shavings “down” the bowl.  Instead, I was cutting “across” the top, which made dangerous “catches” more likely.  Also, I was using way too much force.  So I sharpened up the gouges, re-chucked the bowl, and started making gentle cuts down the center.  No catches!  I needed a lot of patience – it took 2 or 3 hours to get most of the bowl hollowed out – and lots of tool re-grinding (it turns out rosewood is both one of the hardest woods to turn and one that dulls tools most quickly). But I made it through the entire rough hollowing, finish hollowing, and finish shaping without losing it once. I’d actually learned something, and reinforced it through practice.  (Normally I’d post a picture of the bowl, but it’s a gift for a friend, and I don’t want to spoil the surprise. It will make an appearance some week soon)

I still ran into problems – I nearly turned the bottom too thin, and as the walls thinned “chatter” set in and caused some scoring on the inner walls.  It took lots of sanding to get those marks out – I couldn’t manage to do it with a gouge, and had pretty much run out of extra wood to play with (not to self – when I think a bowl wall is a little too thick, it’s probably going to be just right by the time I’m done with finish cuts). But in the end, it’s one of the prettiest bowls I’ve made to date. I took great satisfaction both in conquering my learning challenge and in producing a nice piece.

Now for the second project. A paper for the upcoming conference, that I only reluctantly submitted a conference proposal for in the first place. (Because so many of my projects are collaborative – as opposed to most university work where there’s a single principal investigator and a team of graduate students – I ended up submitting this “for the team”). So from the get go, my heart was not in this paper. I won’t go into a lot of reasons why – it’s enough to say there’s no “juice” in it for me.  But it pays for my ticket to New Orleans next month.

Both projects were struggles this week. The bowl was frustrating and even a bit scary – I just didn’t now how I was going to keep the bowl from detaching itself and launching into whatever happened to be in the way. But taking a break for reflection and re-reading an expert’s writings helped take the mystery out of the problem. I’d probably read this particular book chapter 3 or 4 times, but now (having a specific problem in mind) I paid attention to particular details (the angle of the gouge in particular, and the direction of force) and had an “aha!” moment.

The paper is a struggle in another sense. The only challenge is organizing a very complicated process with lots of moving parts into a coherent narrative. Basically, we’re trying to describe something that on paper appears to be a neat and orderly engineering design/prototyping process, but in reality had lots of fits and starts, a bit of “hacking around” to get us moving, and significant revisions to the original ideas that launched the project.  How to tell this story coherently is a challenge.  It too has some “aha” moments (such as when my colleague helps me remember why we made some decisions that weren’t making sense to me), but it’s not been satisfying to write.

I think it comes down to two qualities, and those are lessons I’ve learned and apparently have to keep re-learning until they become habituated: personal expression and making a difference for somebody.  I get engaged when I’m writing/building/crafting something that has some of “me” in it. The bowl – as simple as the shape was – followed my own aesthetic judgments. The paper feels like a regurgitation of a historical process.  Yes, I had input into that process, and directed portions of it, but it feels like a pretty indirect expression of my ideas.

The bowl is a gift for a couple.  If I’m lucky, they’ll both appreciate it, actually use it, and keeping it as a decorative object will enhance the beauty of their home. The impact won’t really reach beyond them (and their occasional dinner guests). The paper will be read by at least one person (the discussant at the conference panel), and might be downloaded by one or two dozen curious individuals. Will it have an impact on anybody’s (professional) life?  Personally, I doubt it. And if it does, it could easily lead down a path I don’t support (basically, it’s about designing tests for college students, and the last thing we need to do is impose more external testing on institutions).

So tomorrow I’m back to work at my day job, wrapping up this paper and sending it off into the ether. I’ll be in “satisfaction deficit” by the end of this week, and really need to turn my attention to more meaningful work (which, thankfully, I’ll have opportunities to do). I hope to be able to deliver my bowl this week too, and am keeping my fingers crossed that my friends like it. Not for egotistical reasons (although I enjoy a good compliment as much as anyone), but because I genuinely want them to be happy with it. That personal connection means a lot to me, perhaps more than the larger academic audience that might read my “day job” productions.

I’ll close with a favorite line from Ecclesiastes(12:12):

Of making many books there is no end; and much study is a weariness of the flesh.


I’m not a biblical scholar or reader by any stretch, but an old employer/mentor/former book publisher and theologian turned me onto Ecclesiastes.  “Vanity, vanity, all is vanity.”   Basically, my reading of it cautions against “chasing after wind” – acquiring material riches for their own sake, or spouting off to gain in reputation. Overall, it’s a constant reminder that all turns to dust.  Perhaps this isn’t the intended meaning, but I also take from it the reminder that relationships and love – in the here and now – are precious things. While they too eventually turn to dust, they give our lives meaning and depth that mere “production” for the sake of production cannot.

Virtual worlds and messy reality

My “hobby” life and professional life recently crossed paths in an interesting way. It started when the federal government announced a grant competition with one of the possible research topics involving robotics competitions.  (For those not familiar with how research is funded, this isn’t at whacky as it sounds. There are lots of programs in the federal government that hold annual competitions in a broad variety of areas. The specification of focal areas is how the government – and we the taxpayers – have some assurance that research conducted with federal dollars will be important and/or useful. As I recall, the robotics topic was part of a larger program that covers innovative uses of technology in education. Robotics competitions are gaining in popularity, and there is considerable interest in their impact on future science and technology interests of the flesh-and-blood participants).

During a meeting with colleagues we brainstormed some possibly interesting areas of research that would respond to the spirit of the grant. Two ideas in particular were notable for their contrast. One was (broadly) the question of what is gained from having a lot of practical, hands-on experience with mechanical systems. Real robots break and have problem with tolerances; builders need to respect the limits of materials, fasteners, and the laws of physics. Whereas in the 1950’s teenagers tinkered with cars after school, nowadays robots are the equivalent pastime for many students.

The second idea had to do with programming and simulation. Robotics also involves control and planning. In many competitions, the robots have to solve tasks or navigate obstacles without any human intervention. This can require considerable programming prowess to execute elegantly. One colleague (who was an advisor to his son’s team) said kids’ programming tends to be a batch of spaghetti code – long lists of instructions and contingencies sort of hacked together to get the job done.

A colleague pointed out that if we care about kids learning the control/automation side of robotics, then the “messiness” of the physical machines often gets in the way. It’s hard enough to devise an intelligent algorithm for navigating obstacles without also worrying what happens when a wheel inadvertently jams up.  One could imagine kids being overloaded with the frustration of learning to program AND having to deal with clunky hardware (these robots aren’t being designed by engineers with graduate degrees, remember). So he wondered whether a “virtual robotics competition” – where the robots were just simulated avatars a la Second Life – would be an interesting case to study.

On the flip side, others felt that learning about the “messiness” of physical systems, how to improvise solutions, plan for contingencies, etc., were equally valuable lessons, perhaps more important than learning elegant programming habits. Having gotten my start in software engineering, and now being very interested in “learning with the hands,” I could see both sides of this argument. Dealing with physical systems can be very frustrating at times; that was one of the appeals of the “virtual world” when I started in computer science. On the other hand, we live in a physical world, and I wonder what is lost when kids don’t get a lot of experience just interacting with the (non-mediated) world as they grow up.

My thinking is that if you want to teach programming, then teach programming, with or without robotic avatars. Just as we teach Newtonian physics in high school with an emphasis on theoretical models (mechanical systems operating in airless vacuums using weightless strings and pulleys, for example), one could imagine teaching the fundamentals of programming with reference to “ideal” robots or objects.

But to me, there is something special about tinkering with physical systems. I can’t put my finger on it exactly, but I feel like there are some valuable lessons in there, some of which are shared with the programming world (perseverance in the face of failure and frustration; the need for careful planning; problem decomposition, etc.), but others which are entirely separate from virtual spaces (namely, how gears work, what friction “feels like” on different surfaces, the strengths and limitations of motors, etc.)  Just writing these down, I feel a big “so what” question looming – do we really care that youth gain facility with building drive trains? It’s more than that – it’s a “feel” for mechanical systems. Again, I’m at a loss for words. Maybe I’m just being sentimental. But I know I’m not alone in this. Others have been writing at some length on the need to re-integrate the hands into educational experience (e.g., Doug Stowe’s Wisdom of the Hands blog), and some have designed engineering curricula appropriate for elementary school (e.g., Engineering is Elementary).

Actually, I can think of one lesson that differentiates the physical from the virtual – I’ve written about this in the past. The physical world does not have an “Undo” button. Mistakes have consequences. A piece of bad code can be erased and revised in the blink of an eye, but a badly assembled drive train can mean a week of wasted effort.

Read, do, re-read, do…

“The lesson will be repeated until learned.”  That’s the theme of my recent foray into segmented bowl turning. I just had my third disaster at the lathe (for those that are counting, that’s 3 of the most recent 3 bowl projects) making exactly the same mistake as I’d made the first and second time. Does this qualify me as learning disabled?

I posted a short video in my last blog entry illustrating the problem – I made a heavy cut using a chuck (a device for holding the workpiece on the lathe) intended for light finishing passes. The wood is held on largely by friction against rubber stoppers, and any significant shock will tear the workpiece from the chuck. The first time I made this mistake, the bowl shattered. Episode #2 (in the video) resulted in a gluable crack, but the bowl was saved. Episode #3 (yesterday) was only on a ring segment to a bowl, but the ring was large and thick, spun off directly into my face (yes, I wear a face shield for a reason) before hitting the floor and shattering into 3 pieces. I’m pretty sure I can re-glue the segments without obvious flaws, but that’s yet another side-track on this project.

So why do I keep making the same mistake?  Obviously, the lesson hasn’t sunk in, although I’m hoping the 3rd time is the charm. What has struck me, though, is that all of the bowl turning guides essentially warn against this, and I’ve read them all diligently. Book learning was clearly insufficient to prevent this error, and even repeated experience required, well, repetition.  But now when I go back and re-read the wood turning books, the wisdom in their recommendations makes sense in a way it couldn’t have without these disasters under my belt.

My bible for this project (The Art of Segmented Wood Turning by Malcolm Tibbetts) suggests building up projects from bottom up – true the bottom, glue on a ring, true the ring, repeat.  This keeps the working surface co-planar with the bottom and other rings (as opposed to the method where all the rings are flattened on a sander and glued up in a bunch, as I’ve previously done). I fully intended to use that method on this bowl, but somewhere in my excitement to “keep moving” I decided to flatten the main middle ring separately, and that’s when disaster struck.  Using Tibbetts process, the bowl is very securely chucked with proper fastening – using my “modification”, the ring is only attached with a friction fit, and as I realized in the post-mortem, wouldn’t necessarily be flush against the plane of the chuck, anyway.

Enough of the wood turning technicalities. I’m starting to think about instructional guides and their proper use. I have a colleague who is taking an advanced statistical methods class at Stanford, that on the one hand should be “review” for techniques we’ve all been practicing for years, and on the other is intended to revisit them at a deeper level and highlight some of the essential errors and misconceptions we may be unconsciously carrying forward.  I studied under the same professor and encountered many of the same ideas in my first or second year of graduate school, before I had any real-world experience in statistical modeling. While I could follow his reasoning and nod my head, I didn’t have any context for understanding why these were so important (or just not patently obvious). It wasn’t until I’d been practicing in the field for several years that I saw the seduction of statistical shortcuts or the social pressure to use methods that “everyone else thinks are valid.”  Now I can look over my colleague’s shoulder and have a renewed appreciation for what the professor was trying to impart. This wisdom went over the heads of most of his students, not for lack of ability on the part of student or teacher, but because the students simply hadn’t had the years of experience to deeply appreciate why these concepts were so important.

Experts who write textbooks and instructional manuals have the benefit of hindsight – having traversed the ground and scouted out the best routes, they are ready to provide a trail map to the uninitiated. And this is a reasonable approach based in a desire to be efficient – a student should not have to repeat years and years of trial-and-error that the original researchers encountered on the way to enlightenment. My experience as both a self-taught and instructor-taught guitarist has confirmed what a friend once remarked: you can teach yourself the guitar, but you’ll progress 10 times faster if you have a good teacher.  I’m not dismissing the value of instruction.

However, there is an issue of timeliness – when is a student ready to benefit from instruction? I don’t believe this is a linear sequence – my experience with the bowls shows that reading, practicing, re-reading, practicing, etc., seems to be a proper rhythm. This is the basis of what educators call the spiral curriculum – ideas are re-presented cyclically in a deeper and more integrated fashion as the student progresses in his or her learning. So I first learn about chucking wood on the lathe by reading about devices – screw chucks, face plates, 4-jaw chucks, and the like.  I also learn some basic safety rules for using them. Then I go off and work, and eventually violate one of the rules.  Wham!  Wham! Wham! Three disasters later, I’m ready to go back and re-read what each of these chucks can be used for, and in particular I’m highly motivated to understand their limitations.

At a macro-scale, our education system is not well-suited for the read – practice – re-read cycle. Some of this is due to simple age constraints – if we decide that kids can’t do much useful outside of school for their formative years, perhaps we’d better keep them constantly supervised in “productive” learning environments (not that I’m agreeing or disagreeing with this sentiment – just reporting what I observe). But for adolescents and early adults this argument starts to make less sense. Why go through four straight years of undergraduate work when people are still trying to figure out “what works” for them dispositionally, intellectually, and avocationally?  Why not attend, say, a year or two of “foundational” higher education, and then go work for a while, and then come back and continue education when one has proper practical insight and motivation?  Again, I fully understand the practical constraints – it’s hard to interrupt one’s work/career to go back to school full time, there are financial constraints, wouldn’t we just prolong a period of delayed adolescence, etc.  But our current system of 4 continuous years essentially force-feeds a wonderfully rich meal to youth, and hopes that they’ll be able to digest the bulk of it over time, such that years later, they’ll look back and appreciate the value of what they were exposed to, even if they couldn’t fully fathom it at the time.

Just a thought… I wrote a few more paragraphs about the origins of higher education in the US, but then erased them. I was going too far afield for a single posting. For now I’ll just let this basic idea cycle through the back of my mind – the dynamic of reading/doing (and for many, the third leg is “teaching”). Read/do/teach/do/read/do/teach/do….  Time to re-read and repair my bowl and try again.