Strength of supports

my GUESS is the sq tube would be stronger; if you can turn the 90° "down" it may be about the same

I'm not picturing this, how are the four pieces going together.

Regardless, I can't see how you'd have any trouble with any sort of strength with the material mentioned.

John

"Glenn" wrote: I want to use four 7.5 foot lengths of steel to support a

If I am right--you are making a frame to go on four legs, and you want to hold a 4 x 8 sheet on it, they you have ANOTHER choice. Consider placing the square tubing at a 45 degree angle (comparable to the way you would use the angle iron.) I think this would be stiffer than using it flat (and I think it would be stiffer than the angle iron.)

I'm not clear on what you are doing with the "four 7.5 foot lengths of steel" but I prefer tube to angle for most things since a closed section is _enormously_ stiffer in torsion than any open section of equivalent moment of inertia. You might find some helpful ideas in my layout table design: <

Ted

I too am having trouble visualizing the arrangement with four 7.5 foot pieces under the 4 x 8 sheet of particle board. If you are going to run them all lengthwise, that would be a good thing to do, because a simple square frame under the particle board will need support in the middle to keep the particle board from bowing down. As another poster replied, either the box tube or the angle would be very adequate for support. I lean toward the square tubing because it welds better than angle iron and looks better when you are done.

Good Luck, Bob