Circuit boards

[Ken Kelly]

Tom,
	When I heated my Flash chips to the point of melting the
solder, they still had something holding them to the board,
but it was soft enough that when I grabbed the chip with
some tweezers I could rock it back and forth. The chip came
of after a few seconds of twisting. I assumed it was just
the potting compound under the chip. If it was glue, the
heat softened it. NOTE: I was using a commercial heat gun,
not a hair drier.
		Ken

Marc Piccioni wrote:
> 
> Tom
> 
> Usually mass production PCB assembly techniques, under each part is a drop
> of "crazy glue" like adhesive to hold the bit in place during wavesoldeing.
> If you have a PCB that you don't care about try acetone to dissolve the
> potting compound. Usually after the pins are desoldered, a careful
> application of force will crack the adhesive loose.
> 
> /Marc
> 
> ----------
> From:   Tom Sharpe[SMTP:twsharpe at mtco.com]
> Sent:   April 11, 1999 1:54 PM
> To:     efi332 at efi332.eng.ohio-state.edu; diy_efi at efi332.eng.ohio-state.edu
> Subject:        Circuit boards
> 
> 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
> 
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