Re: Polyurethane (fwd)

["Tesla list" <tesla-at-xxxxxxxxxx>]

Original poster: Tesla List Moderator <mod1-at-poodle.pupman-dot-com>



---------- Forwarded message ----------
Date: Tue, 5 Dec 2000 14:24:19 -0500
From: Aric_C_Rothman-at-email.whirlpool-dot-com
To: Tesla list <tesla-at-pupman-dot-com>
Subject: Re: Polyurethane (fwd)

     Acrylic should not be vulnerable to oil-based coatings, provided the 
     product you use does not contain volatile organic solvents to 
     accelerate drying.  I used phenolic varnish, which is oil-based, to 
     coat an acrylic secondary, with excellent results.  I did, without 
     thinking, wipe down the same form with acetone, which did cause the 
     form to craze, but the form, thus weakened, was not damaged further by 
     the varnish.
     
     Do not use aerosol dielectric "varnishes" to encapsulate secondary 
     windings on acrylic forms, as these products are more akin to 
     lacquers, and are full of volatile solvents which will attack acrylic.
     
     BTW, I would encourage everyone to consider phenolic varnish to coat 
     secondaries (at least to encapsulate the secondary windings).  Varnish 
     goes on thicker than polyurethane, and I was able to apply three coats 
     a day with the product I used.  Clean up is with cheap mineral 
     spirits.
     
     Aric
     
     
     
---------- Forwarded message ---------- 
Date: Tue, 5 Dec 2000 11:14:33 EST
From: Esondrmn-at-aol-dot-com
To: tesla-at-pupman-dot-com
Subject: Polyurethane
     
I plan to re-wind my small coil this weekend.  The form is acrylic.  Does 
anyone know if polyurethane (oil based) will attack acrylic?  I know some 
solvents will cause acrylic to crack, like thousands of small cracks 
(craze?).  Does anyone have an acrylic form with polyurethane on it?
     
Thanks,
     
Ed Sonderman