Date:         Fri, 8 May 2015 00:06:47 -0400
Reply-To:     David Beierl <dbeierl@ATTGLOBAL.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         David Beierl <dbeierl@ATTGLOBAL.NET>
Subject:      RapidFix was Re: Wonky temp gauge
Comments: To: "sailingfc @dslextreme.com" <sailingfc@DSLEXTREME.COM>
Content-Type: text/plain; charset="us-ascii"; format=flowed

Ok, it's not baking soda.

The kit "RapidFx dual adhesive system" has two components: Adhesive
and Welding Powder.  Adhesive appears to be a standard low-viscosity
cyanoacrylate.

Welding powder is a noticeably heavy white powder that seems to flow
almost like a liquid in the unopened bottle (a 25 ml plastic
bottle/spout of the adhesive weighs 35 grams; the similar bottle of
the powder weighs about 50 grams).  The MSDS I found online reveals
it as 99% glass, 1% silica.  Under the microscope it is almost
exclusively clear beads, approximately spherical, almost all between
about .003 and .006 inches diameter.  Many (most ?) of them had a
tiny bubble near the center; I doubt that it affects things except to
reduce the density by some fraction of a percent.  It is possible
that the beads were coated with something.  There was an occasional
filament but they were clearly artifacts of production, not an
intentional part of the material.

So -- this is a filled material, not a reinforced one.  I would
expect it to be quite strong in compression but less so in
tension.  Tensile strength might depend strongly on the adhesive bond
to the glass beads.

I'll do a few rough comparison tests between glass and baking powder
fillers when I have a chance.

Yrs,
d

At 08:23 PM 5/4/2015, sailingfc @dslextreme.com wrote:
>Haven't tried this stuff, but it looks to be the same as cyanoacrylate
>(Crazy Glue) and common baking soda.  I've used this combination for years.
>Just sprinkle baking soda on the bead of liquid and you have a rock hard
>glue bead.  Don't use the gel crazy glue, it's too thick and won't absorb
>with the baking soda, which will leave you a blob of crazy glue with no
>baking soda "dissolved" in it.

Great to know.  I have some of the other stuff on order, if it's the
same I'll cuss and let you know.  Either way I'll let you know.  They
also have some light-cured stuff, comes with a UV flashlight.

Yrs,
d