Hi David;
I'll try to address each or your questions below...
<< If the end of a top section is bent a little where many of us have
allowed one leg to stay in the tube below as we tilt the section during
removal is that bend likely to be significant to structural integrity? >>
I would say that the structural integrity is compromised only if the leg
section has become kinked or distorted out-of-round. The steel in the legs
is ductile enough to let you correct minor bends without damaging the
tubular shape.
The biggest problem I can see here is that you'll have a heckuva time
assembling sections involving a leg that is bent more than about a half an
inch or so out of alignment.
Steve at Champion Radio sells a good gadget for this called a Leg Aligner,
which allows you to hook on to both ends of the mating leg sections and
lever them into alignment.
<< What is a best way to straighten a bent leg and maintain structural
integrity? >>
Although I have never had to do this, I would insert a close-fitting pipe
over the bent leg end and gently bend it back into alignment. Align the end
of the pipe with the bent area to apply the corrective bend to the area that
needs it. If it returns to its original shape and alignment with no trace of
buckling, kinking, or other noticeable distortion (usually the case with
small bends), I would have every confidence in it's original integrity.
However, once a piece of metal has been bent many times, it can become
weakened. If you see a leg that looks like it has been bent back to shape,
but still has some residual curves (roller coaster shape), pass it over for
purchase.
<< Is it wise to spray some cold galvanize on any section that has been bent
and straightened in case there are unseen hairline cracks in the galvanize?
>>
The tin is very ductile and should flow with minor bend correction. I would
guess that if a bend is severe enough to crack or flake the galvanizing, the
leg is a goner per above distortion criteria. I don't have enough experience
here since I have never seen this. Perhaps other, more experienced hams
could pitch in here with a comment. The cold galv. definitely won't hurt.
<< 5) Cracks or multiple pinholes in the welds (inspect every weld).
Is a magnifying glass recommended or should these be obvious without
magnification? >>
Good question. Poor welds that I have seen have many pinholes like a sponge
that are easily visible to the naked eye, about the size of a ball-point pen
tip.
<< Thanks again! & 73, DavidC K1YP >>
Glad to help! Long Live TowerTalk!
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