One can usually test the span, and or get a sense if there is any
bending......
It sounds like with square tubing, and 6' you have little flex.
Many engineered beams take advantage of light weight plywood for the
strength
similar to "I" beam trusses....
If a person were to use that in combination with the tubing, no flexing
would happen.
Again, it is a tough picture to see.......
john

"Bill" wrote in message ...

Bill wrote:
The morning I am thinking of a structure based on a "quilt rack"
model--upside down "T" ends, as legs, with a mast of of 3/4" steel square
tubing.
To that I can attach a Loxan polycarbonate box (blade cover), with hinged
front, sides and back--like the box in this video:

http://www.youtube.com/watch?v=cxZOO_zcpNM

As you suggest, I can always improve upon it.



Consider a 72" long beam consisting of 2" by 2" square steel tubing,
1/8" thick, fixed at each end. Assume I attach a 3' beam right in the
middle, perhaps cantilevered, to which my blade guard is affixed. How
much "rigidness" have I bought myself, as far as the beam is concerned?
I believe we are talking about the "strength" of the steel tubing. I
realize that if I shorten the 72" beam, the rigidness will improve, but
how is it doing so far? By comparison, lesser material options that are
available would probably seem flimsy, no? To provide a more complete
picture, I intend that this beam will span an outfeed table.

Thanks!
Bill