[Top] [All Lists]

Re: [TowerTalk] base insulators

Subject: Re: [TowerTalk] base insulators
From: David Robbins <>
Date: Wed, 01 Aug 2012 11:51:02 -0500 (CDT)
List-post: <">>
I agree with thicker plates if you are doing an insulator like that, the ones i 
got are probably 1/2" or so and well galvanized.  the standard roof or pier pin 
plates are meant to be supported on their whole surface not just in the middle. 
 If the commercial stuff is too expensive i would do something with a 2-3" 
thick piece of lexan or fiberglass big enough to support the whole base 
plate... then probably just epoxy it down to the concrete, or maybe put a 
couple of small bolts sticking up an inch or so from the concrete into pockets 
drilled in it, and a bolt in a pocket as a pier pin from the top... that would 
be lots stronger for side stresses than the porcelain like i have.  if i were 
doing the raised one again i would sandwich something like that between the 
plates i have and keep the leg braces for lateral support.

Aug 1, 2012 12:02:55 PM, wrote:


I have pondered using this style insulator but have had concerns as to how well 
they could survive the forces you experienced which led to failure. One option 
would be to fabricate a pier pin to bolt to the top of the insulator so that 
the tower base insulator behaves as a pier pin on which a tower pier pin base 
plate sits, or better yet, a tapered bottom section of tower. My other concern 
lies in the relatively small diameter of the insulator with respect to the 
tower diameter. I would be more comfortable with a wider insulator especially 
at its base and cap. I have seen 1/4" base plates bent because of the forces 
applied between anchor bolts and tower legs. The answer of course it to 
fabricate with thicker plate when the forces cannot be kept linear. 

Jim W5QM

From: David Robbins 
Sent: Wednesday, August 1, 2012 8:08 AM
Subject: Re: [TowerTalk] base insulators

be careful with repurposing old insulators, or even in applying new insulators 
in cases that they haven't been designed for. 

TowerTalk mailing list

TowerTalk mailing list

<Prev in Thread] Current Thread [Next in Thread>