: I've just built a 2x4 box beam as shown in Nicks Book.
: I used 7/16 OSB which I had on hand.
: The beam looks good but it seems wobbly.
: Should I do another one with 1/2" plywood,or will it be OK.
: I realize the strips will stiffen the frame but am I inviting trouble with
: this wobbly spine??? Thanks to everyone on this bb, I've learned lots just
: watching.

Hi Terry

The 7/16th OSB may have been a bit light to begin with. Some folks have even had problems with the 1/2" material sagging. There are a couple of things you can do. If you want to stiffen up the beam, measure the distance from corner to corner (inside the beam) and cut some scraps to fit snugly inside. And you could stagger them the distance of the beam.

You could also just use a couple more supports to hold the beam and eliminate the chance of sag. If need be, use them every 3' or 4'. If they are firmly attached and supported it's not going anywhere.

You definitely want a straight, solid beam, and with the extra supports you can go with what you have. Just get it solidly attached and adjust your forms to align. Hope that helps!

Rehd