Walt,
Having spent the better part of my 25 years as a welder/machinist in
the army "field engineering" (usually field fixes for poor design
"real" engineers put into play) I also am a fan of over building.
Now...having said that...the good captain here has a point that stands
at the very root of field engineering...find an equivalent field force
test. That principle has NEVER failed me (when combined with my 0ver
build habits. There is most definetly a down side to over
building...namely stuff gets too %$#@!! heavy.
In today's "over sue" world, you probably won't find anyone (myself
included) who can promise you 1/8" wall tube will be O.K.. Especially
when we don't have an actual detailed design to look at. I will tell
you that if I'd done the test the good captain did & got the same
results, I'd go ahead & use 1/8" (with gusseting & bracing whereever
possible). Also, I'd tell you...next time look at using some 1/8" wall
chrome-molly (4140) tube...it's good enough for stock car frames! Hope
this helped
-Wayne "Clutch" Glass-