On 2/14/2011 1:27 PM, Barry Merrill, W5GN wrote:
> I had an EZ way from 1976 until 2003 and it was just fine.
>
> It was standing and free upon removal; it took several hours
> of watering/digging/watering/digging and a lot of lifting
> with a rented automotive engine hoist, but it eventually
> came out of the ground.
>
> I dug my hole by hand with a "pole shovel", set that finned
> bottom in the hole and refilled with the dirt, used no
> concrete at all.
>
> I did guy it, first with a 2-el Maco quad, and then I replaced
> that in 1981 with Serial Nr 1 TH-7DXX1.
>
> In 2003, a crane picked up the tower part, but we could not
> pull that finned base out of the ground, (and it was a
> 60 ton crane!); we ended up using a cutting torch to
> remove the pipe part of the finned base where it was flush
> with the ground.
Those bases are relatively easy to get out of the ground even when it's
like concrete, but they typically will not come straight out. and it
does take some patience. It's only about 5 to 5 1/2 feet deep and easy
to lift. Whats not easy to lift is the many tons of packed earth around
it. Until the dirt is loosened it might as well be concrete.
The day before, we used a garden hose to bore down beside the post all
the way to the bottom on all four sides. IIRC we added water several
times over a few hours. Then just let the whole thing soak over night.
Use an auger, or post hole digger to bore between the fins, or just
outside the fins. We used a simple hand powered post hole digger of the
auger type. If necessary use LOTS of water, but not so much you can't
get the dirt out of the holes.
We used a "pair" of engine hoists straddling the post and 4 X 4s
crosswise under the legs of the engine hoists and "choker" chains around
the mast just above ground level. NOTE the 4 X 4s have to be far enough
out to clear the plates welded to the posts! We were finished before I
thought of getting a camera. We applied enough pressure that we could
just see a bit of a bow in each lifting arm ( the arms were completely
retracted to give maximum strength). The next step was to take a couple
of garden hoses and loosen the dirt. We let the hoses bore *under* the
anchor post. The excess water was also loosening the dirt stuck to and
between the fins. You have to watch the hoists as the tension may
lessen as the ground soaks up the water and the pumps to the hoists may
require a bit more pressure at times.
*Eventually* we heard a loud sucking sound and all the water on the
surface disappeared. That darn post almost shot up about two feet. From
there it was a *relatively* easy job to get it out of the hole.
Although a long way from the 60 tons of the crane, (the two hoists had a
combined rating of 8 tons) we just *might* have exceeded that by a
little bit. <:-)) As I have one hoist and a friend/ham who lives less
than 2 miles from me has one, finding hoists was no problem. For two
old guys man handling them into place was more of a problem. Those
hoists with those little steel wheels were meant for a smooth, concrete
floor, not someones back yard.
You can gain a lot of strength in the base by using multiple posts in a
triangle (3), or square (4) on roughly 6' centers and connecting them
with I-beams. If you have access to and know how to use a torch and arc
welder this type of base is relatively easy to make and inexpensive,
although the price of steel has gone up substantially over the past
couple of years.
I recently (Last fall) built a *substantial* 6' "dirt base" to fit a
25G. I used solid 1" rod for the legs and 1/8" steel plates for the
side plates and have about $30 in the whole thing...not counting paint
which I had. I do have photos of that and hope to have them up soon.
NOTE: Disclaimer: This is not a recommendation particularly without the
input of a good mechanical engineer.
Depending on the soil, the spacing between the posts, AND the size of
the connecting I-beams and system you can hold quite a good size, free
standing tower. Also the strength of the base will vary between wet and
dry seasons.
Although strong, the initial strength before the earth settles is only a
fraction of the final strength.
73
Roger (K8RI)
> It was easy to lower and VERY easy to tilt over for
> antenna work; it just wouldn't handle the bigger
> antennas (OB16-3 and Cal-AV 2 el 40), or it would
> still be there.
>
> 73
>
> Barry, W5GN
>
>
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