Box 18 Live Oak Tombstone Stress and Warping

which is a lot to say, kind of.

This box is the eighteenth.  It is made of Live Oak, a wood that I have never worked with.  Like Box 6, it is a tombstone planter, which is to say that two ends of it are shaped like tombstones, and not that one plants tombstones there.  Unlike Box 6, which was of a scraggly Oklahoma white oak and held together with metal screws, this one has no metal, is held together by dowels and glue.

You see the trouble, of course.  The rectangular walls were flatly affixed to the tombstone walls.  Dirt was added.  Was the dirt causative of the warping, or the dirt in combination with the subsequent watering?  A simple theory is that the wetness on the inside caused that side to expand and thus the warping.  I was surprised at the strength of the process, though, that it broke the glue bonds on the dowels.  If I should ever perpetrate this design again I’d be inclined to put more dowels in, and at angles, to see how much power the warping has relative to a fastening method designed to prevent it.

The box is quite heavy, as live oak is just heavy, as compared to conventional oaks.  The janka hardness is 2680, nearly twice that of white oak (1360).  Supposedly America owes its successful birth partly to live oak, of which the USS Constitution was made and off which canon balls bounce.  That’s a game changer.  Assuming this planter does not tear itself apart with these powerful stresses, and that some unforeseen bug nemesis does not appear, it could be that these design mistakes will stand illustratively for a considerable time.

It was a nice wood to work with.  A lot of curves in the grain but a very nice smell, a reassuring strength and density, all bringing a sense that one must be doing something serious.

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