On Tue, 21 Dec 2004 10:08:19 -0800, "Roger Shoaf"
wrote:


jim wrote in message ...
On Tue, 21 Dec 2004 07:16:03 GMT, Flash
wrote:


As a construction type, I think these are good ideas for you but I
think I might make the trusses outa wood because I'm not sure how well
the endpoints of the rods will stay anchored correctly in the wood
especially under tension as the wood ages under the hot sun (rods
don't take compression in theory).


Look at a garden gate. You have an 1/8 or larger rod with a nut and a
washer on each side and a turn bucle in the middle. In the case in
question, all you need to do is to attch eye bolts either the screw in type
or drill through at an angle and use eye bolts with a nut and a washer.

Also the rods are not in compression, they are in tension. The rails are
supported at the ends so sag would be in the middle. Running from the
middle of the lower rail to either the outer edge of the upper rail.

The advantage here is you put your level on the rail and give a couple of
twists to the turn buckle and you are done. 5 years from now if something
sags a couple of twists of the turn buckle and you are back in business.


Also I'd consider inverted V
trusses (at least 2 truss members between posts). The negatives here
might be more costly and more work but I think this will last longer
as well as be stronger.

You are not supporting a second story on a house here you are preventing sag
on a couple of 2X4's 10 feet long. If you were going to make inverted v out
of lumber you might as well just plant another post hole and be done with
it.


That depends on what the OP wants to do. I was trying to make
suggestions based on his post layout now. 2X4's 10 feet long on the
flat is a long span and over the years will sag again so the truss
will take out the sag for a long time.

Also if the rod ends are within the wood and the wood splits the rod
ends may not hold up well especially under tension loads. The trusses
will last longer tho maybe cost more ??