Bolts in concrete (Repost)

[george fremin iii]

WB5M asked about putting bolts in concrete - I had
this post laying around and thoguht it might
be useful.

George
wb5vzl
geoiii@bga.com


From: "Mr. Brett Graham" <bagraham@HK.Super.NET>
Reply-To: "Mr. Brett Graham" <bagraham@HK.Super.NET>
Message-ID: <199603232338.HAA29072@is1.hk.super.net>
To: cq-contest@tgv.com
Subject: Re: setting pier pin for 45G
Status: OR

Here in VS6, everything is concrete.  Therefore, we have occasion to anchor
things into the stuff...
 
For minor stuff, expanding anchors will suffice.  Since they'll never come
out unless you chisel out the concrete around them, the stainless steel
version is prefered.  Waterprooofing hint: put some Araldite (an epoxy
glue) in the hole before setting the anchor.  As the anchor expands, it
pushes the Araldite into all the voids that would otherwise retain water &
eventually wick through the concrete.
 
For any serious stuff - the pier pin for Rohn 45 would probably count - we
use Hilti anchors.  This company makes a literally dozens of different
anchors for concrete.  They have a whole series of chemical anchors which
would be perfect for the application.  They come with either a plated or
stainless steel threaded rod & a glass epoxy-filled cartridge.  Drill the
hole, blow out the dust, drop in the cartridge, drive the rod in with a
hammer to break the cartridge, attach drill chuck to end of rod & drive it
home (which mixes the epoxy at the same time).  About 20 minutes later, you
have an anchor which is stronger than the concrete it's set in.
 
A cartride & rod (non-stainless) costs about US$20 or so here in
over-priced HK.  Due to the abundance of concrete, Hilti actually has
several of its own storefront outlets in town.  So, I'd expect the volume
about cancels the standard excessive mark-up & they should sell for
approximately the same price in the States.
 
One point I'd like to stress - the Hilti anchor is designed as a set.  It's
a special rod intended for the application - I WOULD NOT EVEN CONSIDER
SETTING JUST ANY BOLT IN CONCRETE WITH EPOXY.  QSL?
 
73, VS6BrettGraham aka VR2BG bagraham@hk.super.net


-- 

George Fremin III
Austin, Texas C.K.U.   Sun spots?  I don't need no stinkin' sunspots!
WB5VZL                   Just give me a good Es cloud.
512/416-7010               
geoiii@bga.com