Date: Wed, 08 Dec 2010 05:27:40 -0500
Subject: Re: [TowerTalk] Never before asked question
Petroleum Jelly ,.... Vasoline.... works well, but why worry ... just
pour .. and 12 hours later, remove the wooden frame .. concrete will
NOT be sticking YET.
## I used 4x4's and 2 x 4's around the top of the hole for my
latest tower project. The hole is hard clay, so no forms in the hole itself.
## once concrete cured, a few whacks, and all the wood just came off..cleanly.
IMO, ur wasting your time for 2 x 4's and 4x4's. However, if it's huge
of plywood, that is re-enforced on the outside for strength, I would opt for
any kind of WAX on the inside. Nothing will stick to wax.
## On a similar note, on another concrete install I did back in 1981, a
wood form was built into the ground. We screwed up, and the form was not
The form would start to bulge a bit as concrete was added. [ concrete was
mixer in a rented mixer].
The 'fix' was to add an equal amount of backfill on the outside of the wood
form, and pound it down.
This juggling act went on from 8AM till 11 PM that night. Of my 3 x
helper's , one showed up,
one forgot, and was out of town, and the 3rd was in the hospital with appendix
operation. The only
reason a form was used, was that I had my old 300 gal below ground oil tank
removed, and the new
tower hole and tank hole had morphed into one..too big a hole.
## needless to say, once all done, there was no way to remove the wood form
from the hole, since
it had been completely back filled! 5 x yrs later, and the form still had
not rotted in the ground.
That was the last time I ever mixed concrete in a mixer...no savings there at
all..time wise. With the
rental mixer full to the top, that would provide concrete for 1.5 x wheel
barrows. We dumped 4-6
wheelbarrows of concrete into the hole, and it didn't even cover the bottom of
the hole! We knew then,
this was gonna be a looong day.
## A neighbor across the street told me back in 1997, that if no form used [
say hard clay]... and to keep
moisture from concrete leaching out the sides of the hole, into the
surrounding grnd, the 4 x sides of the
hole can be covered with 4-6 mil plastic sheets. [ bottom of hole is never
covered in plastic sheeting].
This trick works good, and stops the concrete from drying out too fast..below
grnd. I saw on K1TTT's
notebook, another method used, the 4 x sides of the hole are sprayed with
water [ fine spray], just prior
to pumping the concrete in. That method also works good. On this latest
project, I did neither, since the
4 x sides of the hole are fairly hard clay, top to bottom, and moisture
doesn't leach out the sides.
## My problem with any wood form that has to be removed...is the hole has to
be huge to start with.
You have to have enough room to get in there, after 28 x days... and remove
the wood form. THEN
you have to carefully back fill it..and no more than 6" at a time, [called
'lifts'] and well pounded down.
Even then, imo, you still end up with undisturbed soil surrounding the
concrete, which is what you don't want
on any self support tower.
later... Jim VE7RF
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