> The discussion did raise some questions for this novice tower
installer. Hoping to put in a base this spring for a UST TX-472 (4x4x7 cage
...probably weighs about 250 - 300 lbs).
> 1. If the cage is constructed near (not in) the hole, what's the best
way to rig it for lowering it in with a backhoe? Seems to me that just tying
some lift straps to the top horizontals at the four corners might pull the
cage out of shape or pull the horizontals off, particularly if wire-tied
vs welded.
If you've done a decent job and put in the 4 X-braces, it'll shift a
little bit but it'll keep its shape. It'll even be strong enough to stand on.
> 2. There's another rebar cage fabricator further north that has
automated machinery for cutting and bending. Would it be feasible to have them
just cut and bend the pieces, toss them in my pickup truck and construct the
cage on-site? Reason I ask is I'm not sure if building a cage requires
measuring and cutting as you go to deal with tolerances.
YES! Have them cut it. It'll make the job MUCH easier.
> 3. What's the proper way to electrically bond the tower anchor bolts to
the cage to get a good Ufer ground? The anchor bolts are galvanized.
Tying everything up is sufficient.
> 4. Not really a question, but it's annoying that UST requires a 7 ft
deep cage. From what I understand, rebar stock typically comes in 20 ft
lengths. If the depth was 6 ft 8 inch, you could get 3 vertical pieces out of
that 20 ft stock. Perhaps a practical reason for asking about required rebar
lap splice overlap if you have to extend a length.
Refer to question 2. Get everything cut and bent to shape and you
won't have to worry about this. Also have them put in the 8 pieces of rebar
for
the X's.
Cheers & GL,
Steve K7LXC
TOWER TECH -
Professional tower services for amateurs
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