Hello-
I have {1} a report concerning the Cadweld "One-Shots" and a {2} question
regarding attaching solid ground wire to tower legs.
1. I built a all-buried grounding "grid" for a 92' 45-G tower, consisting
of 6 of 5/8" x 10' ground rods. The first 3 were 8' out from base, with a rod
under each guy line. The next 3 were 24' out from base, in same guy line. No.2
solid copper wire { 3 wires} ran from tower base to innermost ground rods, and
then on to outermost ground rods. A 2-wire Cadweld was used on the innermost
rods, whereas a triple hole was used on the outermost rods. The outermost rods
were joined together by #2 wire, with a wire running between each rod forming
a triangle. The first one-shot done was a dual one on one of the innermost
rods. Everything was assembled as shown in instruction sheet, however most of
the molten metal blew out of the bottom of the fixture. The ground rod was
clean { I used the recommended drive sleeve} and polished lightly with fine
sandpaper, the one-shot fixture had the gasket on bottom and it appeared OK.
So, I cleaned up the top of the rod and assembled a second one-shot.There was a
slight amount of coating on the rod top which made the fit a little tighter it
seemed when the second fixture was assembled, and this one did OK. From then on
I placed clay around ground rod, leaving only enough of rod sticking up to
slide the one-shot fixture on, bottomming on the clay.The other 2 innermost
rods were done using dual one-shots OK. When I did the first triple one-shot {
with clay under it} the molten metal blew out one of the wire sleeves. So, I
cleaned this one back -up, assembled another triple one-shot but this time I
packed clay around the entire fixture nearly to the top.This time the triple
made a good weld.I went ahead and did the other 2 triple's in the same fashion,
as I only had 2 of triple one-shots left.Even with packing the clay tightly
around the fixture {esp. where wires entered it} I noticed some molten metal
getting out.
I guess my advice would be to use the larger size wire for the fixture,
sealing up the sleeve area better. Mine were the one-shots for # 1-# 2 solid,
or #2-#3 concentric. As it was I had a hard time finding the # 2 solid, I felt
better using this in a buried application.I could see there was a tiny amount
of gap around wire where it entered one-shot. I hope I can save someone else
the wasted time, money and labor I lost here.
2. I have the #2 solid wire, one up to each tower leg. What would be the
best long-term method of connecting each wire to a tower leg { A bolt junction
it right at base area}. With all I read about corrosion, etc. I want to have it
right.
Thanks, Byron WA5THJ.
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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