[TowerTalk] Adjustments to Tower Base Pier J-Bolts

Richard (Rick) Karlquist richard at karlquist.com
Mon Jul 24 11:47:01 EDT 2017

On 7/24/2017 7:20 AM, Jim Thomson wrote:

> ## Those J bolts he is using, are massive... at  1.875 inchs across, with
> 12 inches  sticking above the concrete.  Paul  did not say how many are used on
> each corner, probably at least 4.    They are not gonna budge, whether a sledge hammer, or
> hydruaulic jack used...or trying to crank up on the lower nuts, trying to raise the template...
> and then trying to bend the J bolts, not gonna happen.

Please explain why the J bolt fabricator can bend the end of the
J bolts into the shape of a "J", but OTOH, the installer cannot put
a very slight bend into them.  With 12 inches above the concrete,
there is something like 12:1 leverage.  Even with 100,000 PSI J
bolts, a 20 ton jack should be able to easily exceed the yield
strength.  I know my jack simultaneously bent 4 one inch braces
without any trouble.  I also had about 12 inches of leverage.

Rick N6RK

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