From: "Marvin Kaye" <marv@lancaironline.net>
Subject: Re: Making epoxy joints - peel-ply
To: lml
Date: Mon, 21 Aug 2006 04:44:59 -0400
Message-ID: <web-1340743@logan.com>
In-Reply-To: <001a01c6c486$045fb240$1429fea9@HPPAVILION>
References: <001a01c6c486$045fb240$1429fea9@HPPAVILION>
MIME-Version: 1.0
Content-Type: text/plain;charset="iso-8859-1";format="flowed"
Content-Transfer-Encoding: 8bit

Posted for "Nicholas Paczkowski" <npaczkowski@telus.net>:

  I have, what may constitute a 'dumb question' but, on the premise that 'you
  will never know until you ask' - here goes.
  
  I use 'peel-ply' on virtually all of my layups. When I peel it off, it
  leaves a nice 'toothy' surface. However when I need to bond to that surface
  with another layup I dutifully sand the area it with 80 grit and wipe it
  clean with acetone. In other words I replace the 'toothy' surface left by
  the peel-ply with a new sanded surface. My question is: "Is this sanding
  necessary"?. Could I just bond to the 'toothy' surface created by the
  removed 'peel-ply without sanding it? Am I getting a better or worse joint
  by sanding it?
  
  Thanks for your guidance.
  

[As long as you leave the peel ply on the intended bonding site right up until 
the very last minute before removing it, the peel-plied surface provides an 
ideal texture for subsequent bonding, one that is well protected from 
contaminants negating the need for any additional solvent cleaning as well. 
 If, OTOH, you remove the peel ply well in advance of bonding it is very 
likely that its surface will become contaminated and require, at the very 
least, a solvent cleaning, and in the worst case, a complete surface prep, 
right down to coarse grit sanding.  I hope this helps.   <Marv>    ]