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What kind of post-post horizontal tolerancing can you hold with those
things, and how is it adjusted or compensated for while driving in?
Usually at least one of the two horizontal surface coordinates has a
reasonably tight alignment tolerance in my experience.<br><br>
They look like a great idea, although one advantage of concrete is you
have lots of time to tweak the post alignments if necessary while the
concrete sets. I would think a helical screw would be prone to
walking just a little, unless the drive apparatus is extremely
well-anchored. <br><br>
John Raynes<br>
RE Solar<br>
Torrey, UT<br><br>
<br>
At 08:45 AM 1/26/2009, you wrote:<br><br>
<blockquote type=cite class=cite cite="">We have also used the local
franchisee of TechnoMetal Posts for many jobs that are ground
mounts.<br>
Around $250 per post is what we paid also.<br>
They were in and out on our last job in 2 days, but their machine did
break down for a while. They placed 32 posts in 2 arrays for a 12.6 kWp
array (60 modules).<br>
We marked the 4 corners of each array & told them how far apart to
place the posts & off they went. Marked, drove, cut off those too
high & welded on extensions to those too short, then ground the welds
& painted.<br>
<br>
We also topped them with Unirac U-LA racking and it lined up well.<br>
<br>
-Glenn<br>
<br>
<b>From:</b> re-wrenches-bounces@lists.re-wrenches.org
[<a href="mailto:re-wrenches-bounces@lists.re-wrenches.org" eudora="autourl">
mailto:re-wrenches-bounces@lists.re-wrenches.org</a>] <b>On Behalf Of
</b>Larry Brown<br>
<b>Sent:</b> Monday, January 26, 2009 7:24 AM<br>
<b>To:</b> info@asappower.com; RE-wrenches<br>
<b>Subject:</b> Re: [RE-wrenches] helical screw piers<br>
<br>
Wrenches,<br>
We used a company called techno Metal Post (
<a href="http://www.technometalpost.com">www.technometalpost.com</a> ) I
believe it is a franchise arrangement with the main company in Canada.
Here is a business opportunity if a franchise does not exist in your
community.<br>
They are screwed into the ground while hydraulic pressure is applied. We
received a stamped engineering report after completion that identified
how many posts were set, to what depth and how much hydraulic
pressure had been applied for load bearing capacity<br>
It requires a special unit designed for this purpose<br>
We set 8 posts in 2 rows of 4 and then attached a UniRac U-LA Ground
Mount racking system for 28 Sanyo 200's<br>
The posts in this case were 2" schedule 40 galvanized steel pipe
ready for the UniRac mounting system<br>
They also shot the elevation and cut each pipe to the proper height so
that the relationship between the front row of pipes and the back row of
pipes was set to receive the racking system and then the mounting rails
would be at latitude for this site. We supplied the heights that
were required.<br>
Many other uses for these screw piers. Pictures on their
website<br>
<br>
Larry<br>
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