"Schertz, William W." wrote:

Paul,
If someone is looking at duplicating or making a beam mount like mine, they
should take a look at the stress formulas for different sections and ensure
that the beam will support the loads. I have included a scan of formulas
that I used.  I set up a spreadsheet and calculated for different
profiles/thicknesses that I could readily buy until I found something that
worked.

Bill Schertz

Thanks Bill. Good idea.
Here is the spread sheet but the pdf is too large to publish.
I'll scan the Roark on just the rectangular section.
Folks save this .xls file as you will need it shortly to use
the Roark formulas.

On second thought I checked my Roark fourth edition 1965
and it does not have the hollow rectangle. Can you scan
just that part Bill. That would also be easier to read
and smaller than the pdf. One can use the solid rectangle and
subtract the inner I but that is a bit much for some people.

BTW if you use the diagonal tube brace scheme none of this is
necessary as the tube is more than strong enough to take
the load.

Paul Lamar

Never mind Bill I captured cut and pasted.

Paul Lamar
 
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