I want to thank the many replies to my question about fabricating the
rebar cage for this HDX-589 MDPL crank up. I have had many good
suggestions. This particular cage specs call for pairs of #13 rebar (1
5/8" each ) for each of the four outer legs, each 8' long. The
horizontal braces call for #4 rebar bent in a square shape (3' 6" in a
side) and each of those goes around the outside of the vertical pairs of
big rebar. To do this to spec, you can't build it in sides or pieces and
put it together. And the pairs of #13 rebar are damn heavy (8 of them
total) so the wire ties have a lot of work to hold the cage together in
any position other than vertical (where the weight is on the ground and
the big "legs" are standing upright)
It appears that the four side big rebar pairs have to be held in place
horizontally to build it, and the small rebar fitted over the big legs
vertically (assemble it on its side), and then tilt it into place with
the excavator or whatever digs the hole. I have had a suggestion to
build a jig out of plywood to hold the sides together during assembly
and then cut it off after the fact, and that might work. I might also
try to figure out some way I could suspend two of the side rebar pairs
horizontally ~4 feet off the ground so I can assemble it all as it hangs
from these sides, and then tilt it vertically to go in the hole. .
Several suggested building it in the hole. A complication is that these
towers are going into packed sand on a mountaintop (a million years ago
the geologists tell me that it was a river-bed before the land had an
upheaval). Although it will hold the base just fine because it is very
hard packed, I have been advised not to get into the hole for any reason
due to the heightened possibility of a wall collapse. So, building it in
the hole will not work.
I have an arc welder so I could spot-weld critical pieces to help hold
it in place. Does anyone know what distinguishes "weldable" re-bar from
"non-weldable" rebar, and what the result of welding re-bar that is not
"weldable".. ( I assume it weakens the rebar below spec.)
This is one of those projects that, looking back over it all, I think
that this is one that I should have paid a specialty fabrication shop to
fabricate for me and let them do the work !! I may yet decide that
discretion is the better part of valor, and take these pieces to the
pros to see if they can put it together for me reasonably.
Thanks all for the help.
Gary W5FI
Gary and Dee Jones
4510 Buckingham Drive
Shreveport, LA 71107-9768
garyejones@cmaaccess.com (House email address)
(318) 309-2139 (House Telephone)
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