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From: "Marvin Kaye" <marv@lancaironline.net>
Subject: Re: [LML] Re: Making a Mold, PVA
To: "Lancair Mailing List" <lml@lancaironline.net>
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Date: Fri, 15 Oct 2004 13:29:10 -0400
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"Jarrett Johnson" <jjjohnson@accesscomm.ca> wrote:


""
His
molds are all a grade A finish inside, and he was having the same 'Orange
Peel' problem with his parts.
""

When I first started using PVA I fought the same orange peel problem.  The 
trick to getting a glassy finish on the PVA is to fog on the first few coats. 
 I tried using those Preval sprayers (the ones that use a disposable cannister 
of compressed gas) and found their dispensed particulate size from the 
spray-can-type nozzle to range from mist to droplets.  The PVA wouldn't flow 
out so it layed on a bumpy surface.  Additional coats wouldn't remove the 
initial bumpiness.  I switched to a standard touch-up gun ran at high pressure 
(70-80 psi) and limited the material delivery to the "just barely flowing" 
condition creating a fog rather than a mist for the first few coats and solved 
the problem.  Works every time.

    <Marv>