Two Skies

It was one of those days where you realize that "sky" is just another human construct, that the sky starts wherever the ground ends.  Sky isn't just something way up out there, but also something that your head is swimming in all the time. 

- John Green in The Anthropocene Reviewed, pg 225

I spent the conscious part of my first 10 years east of the Mississippi* and grew up under a sky that just was -- it did stuff, often unpredictably, and sometimes cool stuff.  The sky was where the weather lived.  It was where my dad worked (he flew fighter jets for the US Air Force); it was where I sometimes dreamed of following him, after reading children's biographies of the Wright brothers and building machines that flew on hope using the bamboo poles that came in our new carpet.  It was where my kites sometimes went and were my dad's model planes usually went.  The sky was where the indecipherable stars were and from whence fathoms-deep snow fell.  It was where the sun strolled and behind which it was sometimes obscured and, once, the stage for its disappearing act.  Like most things when we're kids, the sky was just so, a thing that was there, the way it was, unremarkable until someone remarked on it, seemingly as ambivalent to me as I was inattentive to it.  

Then, concurrent with my father's return for a tour in Vietnam, we crossed North America's Great River to make a home a bare 15 miles inside the edge of the Mojave Desert in southern California -- and suddenly the sky was different.  What made me notice was not the sky itself, but the lack of anything mediating it.  The old accustomed horizon defined by nearby trees, hills, narrow streets, or neighbors' second stories had all vanished, leaving the pale dusty blue to fill the emptiness.  At ten years old, I couldn't have named the difference, but I felt it:  a boundlessness that can only come living in a place where you can always see the edge of the world.  

In the desert, I started my time playing under the sky, chasing lizards and jumping ditches on bikes and mapping out the "unexplored" territory between the base and the Mojave river, boundlessness in the background.  Two years later, the military sent our family to Albuquerque, New Mexico where my time under the Big Sky would settle into a groove.  We lived near the edge of a plateau on the west side of the city in a house with a porch overlooking the valley and the dramatic Sandia Mountains beyond.  My attention expanded with my adolescent capacities and I began to notice more particularly what was going on in that vast sky.  

There, one can watch entire storms, top to bottom, east to west, wend their way across the desert floor.  Curtains of rain -- locally called vigras, as I recall -- hang from the clouds but evaporate in the air in mocking tragedy above the desert floor.  Thunderheads spread their anvils like empires, lit from beneath by the setting sun's fires of war, as evening burns down into sparkling nights.  Two-mile high mountains become speed bumps over which cumulostratus clouds tumble like softly breaking waves.  Usually, cloud bottoms there are about ten or eleven thousand feet, making the sky feel very far away indeed, but once in a great while, they drop, hiding the heights, scraping the world flat like a bottom trawler from Elysium and, though the horizon remains as far away as ever, nothing lives above it.  

In and around the city, the night sky is as light-polluted as in any Eastern town, but, drive for an hour or two in the right direction and, slowly, tiny bright worlds beyond the sky blink into existence.  Go far enough in the winter, when the atmosphere is clean and crisp, and the Milky Way is so bright that you can see the ground by it.  Constellations get lost among the crowds of their quieter brethren; a passing cloud can be easily outlined as it obscures bits of the rhinestoned celestial sphere.  Any sliver of moon glows like a burning brand and its fullness is almost blinding compared to the gentle enfoldment of luneless starlight.  

I lived in Albuquerque for almost fourteen years and consider it home, as much as any Air Force brat has one.  My parents lived there nearly half a century and traveled, leaving and returning to it multiple times, always under the enchantment of my father's wonder of its sky.  In the first decade or so of living there, he flew the city's surrounds more times than I can know and chose the last house he and my mother lived in for the view of what was above the ground.  I cannot visit now without looking up and thinking, "this is my father's sky."  

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Like New Mexico, I never thought to come to Maryland; my path here was, as has been the case most of my life, wandering and characterized by unanticipated futures.  After I left the West, I often romanticized (as above) the vastness, blueness, and starriness of its sky to my East Coast friends.  In the blinding nights of Miami and New York City, I lamented the replacement of the pinpricked dome for a hazy orange one and, lost among the brick and brutalist towers of East Coast downtowns, a flat horizon for a vertical one.  The DC suburbs, however, had a few flavors of my adopted home town:  a tendency to build out rather than up -- indeed, there is a height limit in the District -- and a remarkable accessibility of the country, such that less than an hours' bike ride or a quarter hour by car can find a rolling quietude and relative emptiness in which the heart may take some peace.  

As the exigencies of my life kept me in Maryland, my yen for the sky kept me looking up and, more and more, I found myself surprised by what I saw there:  layered oceans of clouds, not miles up, but mere thousands or even hundreds of feet away; sun pillars, sun dogs, parhelic arcs shimmering and ephemeral; castle wall squalls and level grey cloud mantles.  There is always a show in the sky here and it is never boring.  

I've seen more kinds of clouds here than I knew existed.  Of course, there are fluffy cumulus and gloomy stratus, feathery cirrus and towering nimbus, but also pendulous mammatus, magnificent gravity waves and humorous Kelvin-Helmholtz waves, updraft holes, microbursts, and roll clouds.  And these embedded in large-to-huge weather systems like tornados and hurricanes and derechos, all of which I've seen and lived through here.**  Except for cloudless days, I literally never look up without finding some enchantment made of water vapor wending its way past my ground-perch.  

Even absent of clouds, the sky here parades a kaleidoscope above me.  From the sapphire blues of September -- which, astonishingly, compete fairly with those of New Mexico -- to the pallid wash of a humid summer day, to the pinks, oranges, yellows, reds, indigos, and even greens of a sunset almost any day of the year, I've never lived in a place with such a color wheel above me.  Rays crepuscular and anticrepuscular are to be seen as the sky lowers and Venus' belt lifts, while sunrises burst and sunsets crash in the summer but linger luxuriously through the horizon's naked trees across the winter.  

I'm grateful for our five months of summer, even as I am jealous for more of it, but the weather in the remaining seven of not-summer still draws me into a wondrous fascination, however unpleasant it often is.  During the cool seasons we get, of course, some snow, which I genuinely enjoy (so long as I don't have to move any of it), but I've learned that there are nearly endless variations on frozen and semi-frozen precipitation that other places I've lived seem to lack.  Sleet, graupel, freezing rain, all varying degrees of nasty to be caught in, are nonetheless really interesting both as weather phenomena and as things you might find on your front porch.  I had no idea that there were so many kinds of frost.  Hail is my greatest anxiety -- and not limited to cool weather -- as I have no garage, so it therefore ever-threatens one of my greatest treasures, my car; enough so, that its interest for me as a meteorological marvel is eclipsed by my worries over dimpled bonnets and boots.  

Just as with any metropolis, nights here are mostly dimmed by the brightness of the cities, yet, getting out into the darkness of a country night turns out to be less difficult than it feels out West.  Probably due to the relative nearness of the horizon, it's not so hard to find a place where one can see some of the Milky Way or for enough stars to come out to make identifying constellations a challenge.  It is not like the repleteness of a winter desert night, but it can be enough to recharge the batteries of one's soul.  

I've been in Maryland now for longer than I've lived anywhere else; I anticipate that I will die here.  I deeply love its sky, perhaps more even than that of my desert roots.  A friend of mine is fond of saying, "Maryland gives good sky," and right she is.  I grew up beneath my father's sky, but the endlessly changing sphere here sings to me, making music for my eyes like an infinite organ grinder, ever restless, even when at peace, churning and breathing like the underbelly of an insomniac dragon, ever lit from unexpected angles, at once sparkling and gloomy, purpling like royalty or a bruise, shining as only the firmament can.  

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* The nitpickers among you will remind me that I was born in Texas and lived for two years in Arizona.  Fair enough; however, the only memories I have that might possibly be ascribable to that time are indiscernible from dreams and imagination.  

** The hurricanes that have come through the DC/Baltimore area, of course, are faint shadows of Hurricane Andrew, which my brother and I survived on August 24, 1992 in Miami.  

Rotola: Yeah, Maybe, Maybe Not

In my last post about the rotola -- more than seven months ago now -- I made optimistic descriptions of what would come next and how I'd get those things done.  Well, things have gone well in some ways and not so much in others.  My plan had been to post again once I had the eight strips of the soundboard fully bent, an endcap to attach them to, and an axle to run through the whole thing.  Once I got to the bending part, though, things stopped going according to plan and, given the time elapsed, it seemed like I should post an update, regardless of progress.  

The next step after I left off was to round off the pinblock.  Unfortunately, the best tool for that was one I did not have:  a power sander.  I had had my eye on another Triton tool, recommended by the same YouTuber who sold me on the router I bought, but when I finally had enough cash set aside to order it, it was out of stock.  It finally came in May, though, and I got straight to work making my octagonal pinblock round.  This entailed making sure the center hole was well-centered (it was) and creating a simple jig for keeping the pinblock the right distance from the sanding belt, thus:

I didn't have a dowel the right size, so I made this oak one by hand; I was very pleased with it.  With my new dowel stuck squarely into a piece of hard scrap, rounding the pinblock was quick work:

Now I was finally able to test fit the piece from the first steam-bending test (see previous post) to the pinblock to see if the radii* of the molds I'd made previously were right.  The result:

Nope.  

So, I needed to create a new set of molds.  Given the tediousness involved and mess produced by making the first set of molds (also see previous post), I made a router table using the fancy new router I had previously acquired (indeed, I purchased that model specifically because it works so well under a table).  This went fairly well, if slowly and in fits and starts, and resulted in a very functional table that I'm pretty happy with: 

The router plate and stand are from Rockler; the former I'm happy with and the latter I'm impressed with.  The top is two sheets of 3/4" MDF glued together, making it stable and pretty flat and I ran stretchers across the bottom, which you can't quite see here, to make it very flat.  It's finished with several coats of shellac, so it's hard, and rubbed with Renaissance Wax, so its slicker than snot.  The fence is a piece of angle aluminum and two pieces of oak, held in place by the T-track in the tabletop and T-track bolts with hand knobs, hidden behind the fence in this view.  The T-track is screwed place, rather than glued, so you can slide it back:  the screw holes are several inches apart, so if you slide the track out one screw-hole, you can extend the fence off the back of the table by that distance, expanding the depth of the fence significantly.  I spent quite a bit of time planing and shimming the oak so that the two pieces would be both coplanar and square to the table (I learned too late that angle aluminum is not necessarily square).  I anticipate at some point in the future when I'm better at such things that I'll rebuild the fence and possibly the table to make everything more precise, but it meets my needs for now.  

With the table built, I was able to make new molds with tighter radii and do it faster and more accurately than what I did hand routing the first time.  Indeed, the concave half took me about an afternoon, whereas I spent literal days on the first one.  I did not record the process, but I can describe it simply enough:  Using the fence, I started by routing out the edges of the concavity, the shallowest and outermost sections.  The router table cut much of the work in half by allowing the setup for one side to be identical with the other (by hand, I'd had to set each side individually); it also made the actual routing faster, as I could guide the wood across the bit steadily, safely, and confidently (as opposed to moving the router carefully and wobbly across the wood).  I could then iterate this, moving closer to the center and raising the bit little by little, until I had the curve roughed in.  Too, because of the precision the table allowed, I could cut with a "higher resolution," leaving less needing to be sanded to get to the final shape.  (For the convex half, I used the same method as before, roughing it out on the bandsaw and then rasping and sanding to the final shape.)  

In theory, at this point I could move on to steaming, but I realized that I expected to do enough steaming that it would be worthwhile making a dedicated steambox, rather than relying on turkey roasting bags as I did for my first attempt.  So I built one:

Steam comes in from the kettle via a 3/4" heater hose and a brass fitting. 

The front has a gasketed, hinged door with a spigot to control the rate at which the steam escapes. 

And, of course, one needs a steam source, which is the same one as I used previously, fitted with an adapter I made out of Baltic birch ply to connect the heater hose.

It's wildly overbuilt, with screws and ample glue and sealed with spar varnish.  It does have one leak at the intake end, which I may or may not fix; condensation needs to get out, as well as the steam, so really, it's fine.  Like everything on this project -- actually at this stage of my lutherie -- it's an experiment.  I did look at countless YouTube videos, online posts, and paper magazine articles before going forward with this and my steambox looks pretty much (in some cases very much) like many others out there, which gives me some confidence.  

At this point, it's now late September, so it's taken me six months to get to a place where I can finally start bending some wood.  However, before I risked my precious Sitka spruce (it's not really precious, at $35 a guitar top, but it feels that way, given that it's not scrap), I wanted to run some tests on the system using scrap, so I spent several nights cutting strips of construction lumber into quarter-sawn strips 22" long and 4mm thick (the widths were generally about 1 1/4" or so, but that dimension didn't matter).  I ran a few steam tests and they looked good, drying out almost perfectly the radius of my pinblock:

Most satisfactory!  

Now, I feel confident enough to try my Sitka spruce.  The first result is very encouraging and fits as above right out of the molds.  However, after a day or so of further drying, it loses curvature and is too flat.  My first thought is to make a yet more tightly radiused set of molds, but it occurs to me (not least because I'm not excited about mold making, however expedited the process may be) that I could create a drying jig that keeps the newly unmolded strip at the same radius while it dries.  Accomplishing this took some work:  I discovered that my strips were not all identical widths, so I had to bring them to true; I then learned that the stock from which I cut my jig was not perfectly milled (by me), so I spent some time refining my measuring and planing techniques.  But, after a few iterations, I settled on a design and built a sufficiently accurate jig:

It's very simple:  I used the router table to cut a dado to exactly the width of the freshly de-molded strip into which said strip is pressed.  It worked better than I had hoped, with the strips not only retaining their radius, but shrinking just enough across the grain to release themselves from the jig (they're a tight fit to start).  Now, I could get to work -- and I did.  As of this writing, I have steamed six of my strips.  

Three of them have cracked.  

I have, of course, experimented further with my technique, soaking the strips longer (two-to-three days) and steaming them longer (30 minutes to fill the steamer; 90 minutes of steaming the strip).  I cracked strips #3 and #4 as I played with these parameters, then strip #5 came out perfectly, so I thought I'd sorted it, but while molding #6, I could hear the heartbreaking hisssss-pop of the grain splitting as I clamped it down earlier this evening.  Batting .500 is fabulous in baseball, but it's unsustainable in lutherie.  

For next steps, I have a couple of options.  I'm thinking that one reason the strips are splitting is that the mold is too cold and the strips cool too quickly once they come in contact with it; it often takes me a good 15 or 25 seconds to get to tightening the clamps, during which time the center of the convex half rests against the spruce, cooling it in that one spot.  Not all of the cracks bear this out, though, as some strips have split well off center.  Still, I'm going to try warming the mold with a heating pad before putting the steamed strips in to see if that helps.  I'm also working on a press to push and hold the two mold halves together relatively quickly, then leave me time to cinch everything up with clamps.  

It's possible, of course, that bending thin spruce perpendicular to the grain (most wood bending is along the grain) just doesn't work.  It may be that the properties that make it a great tonewood render it too brittle to be bent in that direction.  If so, the best solution may be to go back to my first idea of a faceted cylinder; my original vision for the rotola has a large diameter, say, 10" or so, and dozens of strings, each of which has a facet/soundboard.  The strips of soundboard would be narrow enough that making them round would be unnecessary; instead the challenge would be getting the angle between each facet right so they join evenly, but that might still be more practical than trying to bend the wood.  

So, from here I intend to continue experimenting.  My goal with this project is to produce a proof-of-concept, not a finished instrument (although I will confess to plenty of fantasies of the latter).  I don't even know yet if this thing will make the sound I want or how to tweak it to do so if it doesn't.  No other option but onward, into the darkness!

* I say "radii" because, in order to account for the thickness of the stock being bent, the mold halves are about 4mm different, inside to outside.