[Boatanchors] MFP (was BC-342

[WA5CAB at cs.com]

Richard,

I don't.  All that I recall is that I only turned up one vendor and that it 
was purpose mixed, not a generic.  A similar search today again turned up 
MIL-V-173C as the late 20th Century spec.  But not the after-application 
solvent for removal.

To maybe answer another question or comment today (about arsenic), my 
search also turned up a Dr. Barry Ornitz reply on a list I'm not familar with.  
He does not mention arsenic.

*********************
From: "Barry Ornitz" <ornitz at usa.net>
Newsgroups: rec.antiques.radio+phono
Subject: Re: voltage rating of enameled wire?
Date: Sat, 6 Jan 2001 20:29:53 -0500

"Gene Warner" <warn at ridgenet.net> wrote in message
news:938ea7$i2v$2 at delphi.ridgenet.net...
> Wasn't the stuff applied to bare copper wires for motor and tranformer
> windings actually called Glyptal? At least most all Govt. Specs called
> for it. I recall ontime looking up the Glyptal Specification and I think
> the dialectric strength exceeded plain electrical varnish by quite a few
> hundreds of volts. The Glyptal I am familar with came out of the can red
> in color. It is also what gives gives the innards of well used govt.
> electronics that distinctive oder. They even sprayed the stuff on
> pre-insulated under chassis wiring primarily to tropicalize the
> equipment. Perhaps if Zenith and other mfgs. had put it on their rubber
> insulated wiring we restorers wouldn't be
> gnashing out teeth today over crumbling insulation.
> R\Gene

Glyptal is merely a trade name for an alkyd varnish.  The name comes from
GLYcerin and PhThALic acid which were combined in a condensation
polymerization to produce the raw resin.  Its voltage rating is no higher
than regular alkyd varnish.  The red color is often obtained by adding red
lead.

The tropical coating is known as MPF, moisture and fungus proofing.  It was
originally an alkyd varnish to which had been added copper naphthnate as an
anti-fungus agent.
Today if you want to recreate this look, especially with military
equipment, use urethane varnish to which has been added some yellow and
green dye.

 *******************************

In a message dated 2/23/2011 9:57:17 AM Central Standard Time, 
1oldlens1 at ix.netcom.com writes: 
> ----- Original Message ----- 
> From: <WA5CAB at cs.com>
> To: <boatanchors at mailman.qth.net>; 
> <boatanchors at theporch.com>
> Sent: Wednesday, February 23, 2011 7:50 AM
> Subject: Re: [Boatanchors] BC-342
> 
> 
> >Some years ago, I researched MFP solvent.  And found two 
> >or three sources.
> >Unfortunately the minimum order was something like 20 
> >gallons and cost
> >several hundred dollars.  The only practical removal 
> >method is mechanical.  And
> >after half a century the best tool I've found is one of 
> >those soldering
> >accessories marketed under tradenames like "Solder 
> >Helper".  The ones with a
> >hexagonal wood handle.  Out of one end sticks a metal rod 
> >with a flat on one
> >side and a tapered and rounded point.  Rod may be straight 
> >or bent at about 30
> >degrees.  The bent one usually works best.  I've seen them 
> >in two rod
> >diameters, about 3/16" and about 1/8" diameter.  Out of 
> >the other end is another
> >rod of the same diameter terminated in a brush or a slot 
> >(for bending wire)
> >or maybe other things.
> >
>       Have you any memory of what the solvent was or was it 
> not a generic one? I have never found anything that takes 
> the stuff off easily. Paint rememover will eventually get it 
> off but it may take many hours of repeated application, 
> certainly not very practical for wiring. Most of the time 
> the soldering iron will burn it off but then you must clean 
> the residue.
> 
> 
> --
> Richard Knoppow
> Los Angeles
> WB6KBL
> dickburk at ix.netcom.com 
> 

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