[Towertalk] plywood templates

K7LXC@aol.com K7LXC@aol.com
Thu, 1 Aug 2002 11:31:21 EDT


In a message dated 8/1/02 8:16:48 AM Pacific Daylight Time, 
richard@karlquist.com writes:

> I poured two bases for MA-550 poles,
>  which have 4 bolts, in a square
>  about 6 inches on a side.
>  In both cases, the J-bolts migrated
>  inward about 1/16 to 1/8 of an
>  inch, despite having them bolted
>  to a template made from a 2x12.
>  The bolts were very tight against
>  the inside of the holes in the
>  wood.  I attribute this to concrete
>  shrinkage.  It certainly wasn't due
>  to "nudging".  I was lucky that there
>  was enough slop in the base to get
>  the bolts into the holes anyway.

    Having just one template can be a problem as you've described. Using 2 
wood templates is one way to get around it. What I do is to take the bolts 
attached to the template to my neighborhood welding shop and have them tack 
weld some rebar to the anchor bolts. That way NOTHING'S gonna move and it 
makes it real easy to attach it to the rebar cage or otherwise deal with it 
with without disturbing the proximity of the bolts. 

    When you get it home you can try it on the tower base to insure proper 
fit and then "Bob's your uncle!".

Cheers,
Steve    K7LXC
TOWER TECH -
Professional tower services for commercial and amateur