Gunner wrote:

I have a good quantity of 16' long 4x8s and 11 joints of 3" pipe, 11
feet long. I have 50 pieces of 5" C channel, about 4' long.


Id rather make the thing free standing, so it could be disassembled
and moved

You asked..and keep in mind this is me, and if I was normal I wouldn't
be here.

First of all, do you really mean a _flat_ roof? You might want to put
some slope in it to let the rain run off.

For the bents: you have 16' timbers that you want to use for joists.
That means that allowing for overhang (and a little for the slope), one
of your dimensions will be limited to about 14'. If you used a 7' span,
and made a framed opening, you would use 9 of the pipes. Use some of the
channel for diagonal bracing. The remainder gets used as a welded
together H heam around the base.

This is where it gets peculiar. The Santa Anas blow through there, and
you don't want this thing to be launched into the house, but you need to
move it. Dig some fencepost type holes to go under the H beam foot. Fill
them (below grade, you may want to hide this later) with concrete and
place a rebar U and a mounting plate on top. On the mounting plate,
mount the axle and 4" wide wheel assembly (made of wood, aluminum or
whatever) facing up. When you place the H beam on it, it makes an
inverse track. Weld an ear to the upright beam and run a piece of steel
cable (you did say oil country) through the rebar U in the concrete and
the tab. Secure the cable with clamps. When you need to move the
structure, loosen the cable and push the structure out of the way. You
could forget the wheels and just use sections of pipe as rollers, but
that isn't as much fun.

If you ask tomorrow, I'll have a different plan.

Kevin Gallimore