[TowerTalk] Tower ACCIDENT

[jeremy-ca]

WOW, Ive removed and reused many base plates including a few that were 
within 100-200  yards of the ocean and never saw one that bad even after 
20-25 years. Id suspect a concrete that has a higher concentration of salts 
than normal leaching out over the years.

Ive also had many sections regalvanized that were covered in surface rust 
from being in very exposed locations and also subject to acid rain. The 
interiors were still perfect.

Carl
KM1H



----- Original Message ----- 
From: "Tom Anderson" <WW5L at gte.net>
To: "jeremy-ca" <km1h at jeremy.mv.com>
Cc: <towertalk at contesting.com>; "Jim Lux" <jimlux at earthlink.net>
Sent: Thursday, June 28, 2007 1:06 PM
Subject: Re: [TowerTalk] Tower ACCIDENT


>
>
> A word about using Rohn's flat plate mounts.
>
> Several years ago I helped the XYL of an SK dispose of her OM's ham 
> equipment.  One of the last things sold was his 60 feet of Rohn 25 tower. 
> It was attached to the concrete slab which was like 4x4x6 by one of Rohn's 
> flat plates and bolts at each corner.
>
> She didn't want the mounting plate left, but would be ok with the slab, so 
> we used a sledge to knock off the thoroughly corroded bolts and once we 
> removed the mounting plate we saw that it had nearly corroded through on 
> the bottom side to the top, although from the top the corrosion wasn't 
> visible.  Apparently the slab wasn't flat or crested to allow water to 
> flow away from the plate.  It pooled underneath and the years of water 
> being present had corroded the plate to the point where within a few 
> months it might have failed and the whole 60 ft guyed tower had come down 
> when the base slipped.
>
> Tom, WW5L
>
>
>
>