I think we have some different information.
I have a 45G http://www.rogerhalstead.com/ham_files/tower.htm
On http://www.rogerhalstead.com/ham_files/ground.htm the left side photo on
the next to the bottom row shows a junction between the tower leg and base.
These are definitely a "slip together" joint.
> I couldn't disagree more. First, the coating is zinc not 'galvanize' which
is a process. Second,
ROHN uses a double "hot dip" galvanizing process according to their
catalog..
>Julio mentioned using Rohn 45 which does not slip together instead each leg
has a welded
> plate with 4 bolt holes and the tower sections stand one atop the other.
Dan's concern about >the legs becoming clogged with zinc is a valid concern
but unlikely with Rohn 45 because the
My 45G does not use joining plates, but rather the legs have a larger tube
welded in place that slips over the tower leg. They refer to it as a
"sleeve joint". The tower legs are not swaged. Even the 55G uses a
"sleeve joint".
Remember there are two different ROHN 45G towers. The hollow leg and solid
leg. The solid leg are heavy!
They did not easily slip together from the factory. Even at 90# each they
had to be "worked" down into place. Following the factory directions I used
taper pins to enlarge the bolt holes and force the tower legs into
alignment.
One of the first things they say is "do not drill out bolt holes to make
them fit! Drive a taper pin in to enlarge the holes".
> legs are rather large in diameter. If Julio can find someone in his area
with the capability to
Like you, I seriously doubt the legs would plug if done properly.
> recoat the tower sections I would suspect it will cost a great deal of
money. If the tower
To have some one set up to do a single batch of hot dip galvanizing would
probably cost more than the tower new, but if you could find some one using
the process, they might be able to slip it in. OTOH, they are going to
insist the tower sections be absolutely clean inside and out. They might be
able to "pickle" them.
Were it me, and it's not, I'd thoroughly scrub out the tower legs using
something like the pipe cleaning brushes on a long drill while flushing with
plenty of water. Then thoroughly dry. Get a few gallons of the cold
galvanizing and a good spray gun, or tape the bolt holes shut, plug one end
of the legs and pour it full of the cold galvanizing. I prefer half to
three quarters full and lots of sloshing. Don't forget a large drip pan!
<:-)) Pull the tape off the bolt holes while the legs are draining. Hang
vertically so they will thoroughly drain and leave them in the hot sun to
help dry.
This is not a bad idea for the smaller towers as well, but those legs need
to be clean inside.
You might be looking at a couple hundred dollars plus hardware.
You can purchase new grade 5 SS (or galvanized) bolts, nuts, and washers
under $40 total for the whole tower.
> sections are in good shape I would suggest leaving them alone but replace
all the mounting >hardware with galvanized nuts, bolts, and washers (I don't
recall the spec right now but their is
I never reuse tower bolts.
Grade 5 is good. Otherwise you can get them from ...er ... could get them
from ROHN. Galvanized, or SS Grade 5 work fine. SS Grade 5 is cheaper for
a box full at a bolt supplier, than purchasing half a dozen galvanized from
some of the building supply places.
The two sizes needed (5/16 and 7/16 as I recall) are relatively inexpensive
when purchased that way.
> one common to hardware suppliers). My club recently installed 100 ft. of
used Rohn 45 at approx. 3500 ft. near the Pacific Ocean. We replaced all
hardware, cold galvanized all dings and
> marks during assembly, and torque all hardware 3 times over a 6 week
period (3 visits to the site). They are in great shape and some of the
sturdiest I've ever climbed. Hope this helps.
I checked mine, but never had to retorque any bolts.
Using Phillystrand guyline I only had to retension once and even then they
really weren't out of spec. You do need to periodically check to make sure
the ends of the guyline are sealed. Moisture will ruin the strength of
Kevlar.
Roger Halstead (K8RI, EN73 & ARRL Life Member)
N833R, World's Oldest Debonair (S# CD-2)
www.rogerhalstead.com
<snip>
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