FW: [R-390] Flux Solvent Question

Tue, 25 Jun 2002 14:02:09 -0400

Isopropyl alchohol is OK if the flux is reasonably fresh. For old dried on
residue, acetone works well. We use both at work on microwave PC material.

The assemblers also use TECHSPRAY "AMS GENERAL DUTY FLUX REMOVER".

At home I use GC "FLUX-OFF".

As with any solvent test it first as some plastics may be affected.

One thing NOT to do is use any cleaner such as Simple Green, Super Clean,
Scrubbing Bubbles and the like around HV. It will result in HV breakdown,
particularly on phenolics.  I learned this the hard way when I tried
cleaning a SB-200 power supply board. Flushing with alcohol or water didnt
help since the product was absorbed into the pheonolic.

With any solvent or cleaner, have plenty of ventilation and wear gloves/eye
protection as appropriate.

Carl
KM1H

-----Original Message-----
From: Glenn Little [mailto:[email protected]]
Sent: Tuesday, June 25, 2002 1:18 PM
To: Scott, Barry (Clyde B); [email protected]
Subject: Re: [R-390] Flux Solvent Question

Barry and the group,

It depends on the flux.  Most flux that you will run into is RMA (rosin 
mildly activated).  This can be removed with a flux cleaner specifically 
formulated for to job, or by denatured alcohol.  This is not the 70% that 
you get at the drug store. You might be able to find 91% at the drug 
store.  THis is fine.  You can also get denatured alcohol at the paint 
department of your local store.  If you get into a bind, Vodka or everclear 
from your local spirits shop also work fine.  If the flux is unknown you 
mighr want to try water first.  There is a noclean flux that requires 
special treatment to remove.  If you start to see a white liquid when you 
apply alcohol, you have a noclean flux.  Do not go any further with the 
cleaning unless you want to get the correct chemistry or you want to use 
lots of alcohol.

I usually tilt the board against something on the bench with some paper 
towels under the edge of the board.  I then apply alcohol at the top of the 
board with cotton swabs.  This lets the flux saturated alcohol collect on 
the paper towels.  I continue with the alcohol bath until the board is no 
longer sticky.

Hope this helps

73
Glenn
WB4UIV

At 09:48 AM 6/25/02 -0500, Scott, Barry (Clyde B) wrote:
>On the subject of soldering, what is an appropriate solvent to use to 
>remove excess flux?
>
>Barry(III) - N4BUQ
>_______________________________________________
>R-390 mailing list
>[email protected]
>http://mailman.qth.net/mailman/listinfo/r-390

---------------------------------------------------------------------------
Glenn Little                         [email protected]   QCWA  LM 28417
Amateur Callsign:  WB4UIV            [email protected]   AMSAT LM 2178
QTH:  Goose Creek, SC USA (EM92xx)                      ARRL  TAPR
---------------------------------------------------------------------------

_______________________________________________
R-390 mailing list
[email protected]
http://mailman.qth.net/mailman/listinfo/r-390