[TowerTalk] Adjustments to Tower Base Pier J-Bolts

Steve Maki lists at oakcom.org
Sat Jul 22 20:36:20 EDT 2017

OK, but since Pirod's design spec, or instructions as it were,  (and I 
love Pirod, believe me) is already faulty as you know, we are seeking 
after-the-fact solutions.

First, there is no need for the bottom nut to be 1.5" above the concrete 
for leveling purposes. Unless your concrete is slanted severely for some 
reason. Put all your nuts down to the concrete. Find the highest one. 
Bring the others up to that level. You know where I'm going, right? 
That's going to save you at least an inch or more.

Next, get rid of the lock washers. They are useless.

Next, disabuse yourself of the need for the 3" of threads showing on top 
of everything for *leveling*. Not needed. If your bottom nuts are level, 
you can get by with a 1/2" on top.

The critical task is to get the bottom nuts level. A laser level, or 
just a long straight edge and bubble level is all you need.

-Steve K8LX

On 7/22/2017 20:06 PM, Paul Christensen wrote:

> Several folks want to know why there's 12" of exposed bolt above the
> surface.  That's Pirod's design spec., but also keep in mind that a
> self-supporting tower base foot does not rest on concrete.  It actually
> rests on a nut as a leveling device.  The nut under the foot is adjusted to
> level a self-supporting tower.  So, here's the actual length needed:
> First, the nuts are all 2" in height and the bottom nut is spun to 1.5"
> above the concrete surface -- again to allow for leveling. Next, add a high
> strength flat washer, lock washer, followed by the height of the tower foot
> which is 3.0".  We then add more hardware and another nut to the top.  All
> the washers together are 0.5" in height.  So we end up with:
> 1.5+0.25+2.0+0.25+3.0+0.25+2.0 = 9.0 inches, leaving 3 inches at the top.
> Probably the most I'd ever cut is maybe 1 inch off the top and that means
> cutting 1 inch off of four extra-high-strength steel bolts is almost
> certainly not worth the effort.

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