>From this morning's Boulder Daily Camera:
Austin Healey 1967 3000 BJ8, #2 condition, $20,500
'60 Triumph TR3A No rust, partly restored, factory steel hardtop, $3350 obo.
On the garage reinforcement question, the reason Pat's plywood idea is
right is that you need the cross (vertical) grain wood to resist the
shear forces in the center of the beam. A roof joist is just like an
airplane spar, which I've built many (small ones) of. The top and bottom
of the beam are in compression and tension respectively, while the
middle is loaded in shear. Wood is strong along the grain and weak
across it, as we all know. The roof sagged originally, not because
the beam was insufficiently strong in tension or compression (it would
have failed if so) but because it was insufficiently *rigid* in shear.
Model glider spars are spruce or carbon top and bottom with vertical-
grain balsa in between.
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