I made this mistake some years ago with 7 cu yds of concrete and a 48 foot
self supporting tower. The forms disappeared, the base shifted causing the
tower to lean and being out of plumb at the top by about 7".
I ended up pouring another base, 10 cu yds this time to fill in some side
cave-ins, without forms, moved the tower over using a boom crane and the
base hasn't shifted in four years and never will.
73, Carl VE9OV
----- Original Message -----
From: "Jim White, K4OJ" <k4oj@tampabay.rr.com>
To: "EUGENE SMAR" <ersmar@comcast.net>
Cc: <towertalk@contesting.com>; "Rich Hallman - N7TR" <rich@n7tr.com>
Sent: Sunday, June 29, 2003 9:44 PM
Subject: Re: [TowerTalk] Using plywood forms...??
> Gene...
>
> Are you saying the 1/2" or 3/4" of plywood around the pour once it
> disintegrates will create a void that wide between the earth and the
> pour???? And then the concrete mass could shit by 1/2" or 3/4"
>
> I seriously doubt that... and think nature wouldfind a way to make up
> for the "slack" as rains came and went the soil would ultimately be
> found near the pour...
>
> Jim, K4OJ
>
>
>
>
> EUGENE SMAR wrote:
> > Rich:
> >
> > Absolutely remove the form. If you don't, when the wood decays,
that
> > side of the foundation will not have the support from undisturbed earth
that
> > the other sides have.
> >
> > This means that you'll have to allow sufficient room around the
> > foundation to get at the wood for removal. That, in turn, means you'll
have
> > to backfill the void. And finally, that means you'll have to compact
the
> > backfill as it's being dumped into the excavation. Don't just shovel in
the
> > dirt and walk away. After each half a foot or so has been shoveled in,
> > punch at it with the end of a 2X4 until it doesn't compress any more.
Then
> > shovel in the next half a foot, etc.
> >
> > However, it might be easier if you just fill in the oversized hole
with
> > a bit more concrete. You'll avoid the need to worry about forms,
removal,
> > compaction, etc. The hassle is a toss-up between excavating exactly the
> > right sized hole vs buying and placing a bit more concrete.
> >
> > 73 de
> > Gene Smar AD3F
> >
> > ----- Original Message -----
> > From: "Rich Hallman - N7TR" <rich@n7tr.com>
> > To: <towertalk@contesting.com>
> > Sent: Sunday, June 29, 2003 3:11 PM
> > Subject: [TowerTalk] Using plywood forms...??
> >
> >
> >
> >>I'm installing several Trylon T400-80's. I noticed that you can use
> >
> > plywood
> >
> >>forms for those times when your backhoe guy gets carried away with the
> >
> > hole
> >
> >>digging.
> >>
> >>If I use a form for one end of my oversized base.....Do you remove the
> >>plywood, then backfill.....Or backfill with the plywood in place?
> >>
> >>Thanks...
> >>Rich
> >>
> >>www.n7tr.com
> >>
> >>_______________________________________________
> >>
> >>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.
> >
> >>_______________________________________________
> >>TowerTalk mailing list
> >>TowerTalk@contesting.com
> >>http://lists.contesting.com/mailman/listinfo/towertalk
> >
> >
> > _______________________________________________
> >
> > 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.
> >
> > _______________________________________________
> > TowerTalk mailing list
> > TowerTalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
> >
>
>
>
> _______________________________________________
>
> 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.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
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