Here is a slightly different geometry folded up from 0.90" thick
4130. The geometry is simpler and easier to fabricate. I put two hems on
the top edges (instead of flanges.) This should make it a lot easier to
fold up in the bender. I didn't bother to clip the ends.

         The weight is 5.4 lbs. This is about 1.4 lbs heaver than the
original design. It has a significantly greater factor of safety. (At least
in the simulation.) You could drill lightening holes in the blue areas of
the simulation if you wanted to reduce the weight.

         I would suspect that you could fabricate this style beam for less
money than it would take to weld on the key stock and mill out the
clearance slots in the original design. I could be mistaken though.

         I should note that the deformation shown in all the pictures is
magnified. In these pictures, it is magnified by a factor of 13. In the
previous pictures, it was magnified by a factor of 17. If I set the
magnification to 1, then you would not be able to easily tell how and where
the beam was deforming. The true deformation is so small that would not be
able to see it in a picture.

         Again, use your own judgment in interpreting these simulations.

Bill Dube'

We won't be doing any .090 in the foreseeable future as we already
have a bunch of .063 beams. It takes a big press brake and punch to bend
and punch .090 4130. My friend that did these for Jerry can't handle
it.  Also a lot more money for material. The price of 4130 has gone
up recently and it was in short supply for awhile.

Paul Lamar

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