Circuit boards

[Ord Millar]

MG Chemicals conformal coating stripper, cat #831 is usually good for this.
It's really thick, so it's easy to get it just on the area that you need to
work on.  It's a little bit aggressive, so you can't leave it for too long
on the board.


-----Original Message-----
From: Ken Kelly <kenkelly at lucent.com>
To: diy_efi at efi332.eng.ohio-state.edu <diy_efi at efi332.eng.ohio-state.edu>
Date: Sunday, April 11, 1999 11:48 PM
Subject: Re: Circuit boards


>Tom,
> I socketed the flash chips on my 95 Camaro LT1 PCM. It had a clear
>waterproofing all over the board. This seemed to also be under the chips. I
>built a copper foil damn around the Flash chips, then used a heat gun to
remove
>the surface mount Flash chips, The heat from the heat gun melted the solder
and
>softened all the goo up so I could pull off the chips. I then cleaned up
the
>area with repeated cleaning with alcohol. Alcohol did not really disolve it
,
>but with scrubbing it cleaned the board up enough to allow me to solder on
the
>sockets.
>
> Ken
>
>Tom Sharpe wrote:
>>
>> I have a couple of EEC_IV boards that I am trying to disassemble. The
>> CPU and ROM  seem to be glued down then sodered into place. There is
>> also a heavy, clear coating (waterproofing?) over everything.
>>
>> Does anyone know what will disolve this without destroying the board?
>>
>> How about the glue?
>>
>> Thanks in Advance   Tom Sharpe
>