[GreenKeys] [R-390] Removing MFP (fwd)

[Richard Knoppow]

----- Original Message ----- 
From: "Jim Haynes" <jhhaynes at earthlink.net>
To: <greenkeys at mailman.qth.net>
Sent: Saturday, March 24, 2012 7:56 PM
Subject: [GreenKeys] [R-390] Removing MFP (fwd)




---------- Forwarded message ----------
Date: Sat, 24 Mar 2012 19:51:36 -0700 (PDT)
From: Perry Sandeen <sandeenpa at yahoo.com>
To: r-390 at mailman.qth.net
Subject: [R-390] Removing MFP


Some of the BA’s we have/get were coated with MFP which 
causes several problems.

Background.
A long time ago the US military found it had a problem in 
some situations with mold and/or fungus thriving inside 
electronic equipment so they developed a spray material that 
was applied to combat the problem. It is a brownish looking 
material on wires and solder joints and adds a somewhat 
golden look to aluminum chassis parts

Our current problems with MFP
Wires and terminals coated with MFP makes repair difficult 
as the wires become stiff and tend to glue together in wire 
harnesses.  Sometimes adding to the problem is the spray 
coating was very heavy.

Terminals covered with MFP must be scraped clean before 
soldering or one gets an ugly residue.  Scraping the stuff 
off can be difficult.  I’ve found that a stainless steel 
cuticle pusher, about $4 at beauty supply stores, sharpened 
a bit on a grinding wheel worked best for me.  I tried using 
a Xacto knife.  For me in many cases the blade was too large 
or wasn’t good for prying, but then it wasn’t designed to 
pry.

I had no success with either alcohol or acetone.  A list 
member suggested AFAICR, Goof-Off.  I tried it but it didn’t 
work on the MFP. I’m still looking for a chemical cure that 
isn’t a carcinogen.

Removing MFP from aluminum parts.
For removing the stuff from chassis parts thanks to Walter 
Wilson, I learned of an automotive product called NEVER-DULL 
by Eagle One.  It is about $5 for a 5 oz. and comes is a 
round metal can.

It is a bit of a strange product.  It seems to be cotton 
wading moistened with a faint kerosene-like odor fluid.  To 
use it, one pulls out a wad and then rubs the MFP coated 
metal.  The wading turns black in color as you rub.  You 
keep moving the wadding around until the whole piece is 
black. The results are spectacular.  Now the downside is 
that this takes a great deal of time and can be expensive. 
To do both sides of one R390A side panel might consume a 
whole can and several hours.

Somewhat faster (relatively speaking) and considerably 
cheaper was using a product marketed by Turtle Wax called 
POLISHING COMPOUND & scratch remover.  It is a white cream 
with some abrasive in it so the finished shine was a bit 
duller than using NEVER DULL.  I have yet to try using NEVER 
DULL as a final polisher for metal done with polishing 
compound.

For very heavy MFP or corrosion I used The Turtle Wax 
product rubbing compound. This is a rust colored paste that 
removed MFP fairly rapidly.  It is about the same price as 
the polishing compound but leaves a duller finish.

The level of finish “shine” desired is totally subjective. 
The amount of MFP applied seems to very greatly.  My best 
advice is to try any or all of these products in an 
inconspicuous place and see how they work in your particular 
situation.

A final note.  I also tried these products on an old plain 
SP-600 side panel and got the same results.  IMNSHO, I 
believe any BA metal polished with these products makes for 
a very good looking radio.

Still on the to-do list is to see if front panel paint can 
be shined up with the NEVER DULL or the polishing compound. 
I personally wouldn’t use rubbing compound on a painted 
surface because it is so aggressive.

Perhaps others would share their experiences.

Regards,

Perrier

     I ran into a serious problem with MFP on an SP-600-JX. 
The stuff had been applied very liberally, it had glued the 
modules into the turret.  It was also coating the grounding 
surfaces in the turret.  I have not found anything that 
takes this stuff off readily.  The most effective solvent 
seems to be paint stripper but it takes several applications 
and a long time.  I've tried all the more common solvents 
including n-heptane (rubber cement thinner) with little 
luck.  The paint stipper does work given enough time.
     There are a number of "rubbing compounds" available at 
auto supply stores.  I am not sure what is in Never Dull but 
the rust color suggests it has rouge in it which is a mild 
abrasive.  I am not sure a plain rubbing compound would be 
helpful with removing MFP although it might shine up a 
chassis.
     The MFP coatings were made before it was required to 
list ingredients but perhaps someone knows what the original 
carrier solvent was.


--
Richard Knoppow
Los Angeles
WB6KBL
dickburk at ix.netcom.com