Not trying to make anyone look bad or wag a finger, but I think there is
an important lesson here that no one has mentioned.....
ANY tower or antenna should be inspected at least yearly for loose
bolts, rivets, etc. especially when installed in a windy environment.
The original poster said the tower had been up for 15 to 20 years without
a problem. Well, I suggest that the loose bolt problem which is causing
the current concerns could have been avoided if the bolts had been checked
and re-tightened on a regular basis. I'll lay a bet that the bolts had been
loose for at least a couple of years if the bolt holes were elongated as
described, maybe longer.
HBX/HDBX tower is a bear to climb and maintain due to the X-bracing.
There are many things I had rather do than climb one of my HDBX towers
for inspection purposes, but it IS NECESSARY if I want my installations
to be safe and last through the Oklahoma winds. This series tower
exhibits uneven galvanizing and surface rust will form. I use the inspection
trips to lightly brush any rust spots and spray them with cold galvanizing.
I have used HDBX towers for over 20 years and have not had any failures.
The top of my unguyed 56-foot tower is more steady than most guyed Rohn
25 towers I have climbed to help fellow hams. The largest beam I have had
on the towers has been a HyGain TH5Mk3 with a 20-foot boom. I lost the
beam in a 95-mph straight line wind two weeks after an ice storm which
coated the beam with almost two inches of ice for 8 days. The tower
sustained no damage at all. The HAM-IV was completely destroyed.
I now perform all my tower work from a 60-foot Snorkel man lift I bought
in 2000. My 65-year old knees told me it was time to quit climbing. My
feet agreed and said I should not subject them to the HDBX X-bracing any
more.......
To repeat (us old farts have to do that!).....any tower/antenna installation
needs regular maintenance. Failure to do so WILL result in problems
and safety issues.
Be safe......73.....Jim W5JI
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