I think most people's objections are the expansion-contraction of
them and how that interacts with the coverings expansion-contraction
rates. The general construction steel framing studs are also a bit
large for small trailer use and their dimensions are not easily changed.
If I recall - from my Whole Earth Catalogue browsing days - there was
something called Unistrut that was a square section tube with evenly
spaced holes, that could just be bolted together to build whatever
you wanted to [Whether it was pretty or not is another matter.].
I just Googled that:
http://www.unistrut.us/index.php and
http://www.unistrut.us/index.php?WP=LItLibrary - if that is
the same one I'm thinking of, and found there are other shapes available
too now, and they even have a fiberglass version of them now - there is a
build in the build journal section where an ultra light TD was done with
some fiberglass framing members included. Either the regular steel or
these fiberglass struts may be a bit pricey [my speculation] but they may
be worth it, especially for the small amounts needed in a TD/TTT.
Cheers,
Norm/mezmo
If you have a house - you have a hobby.