I don't think flux residue is the only problem. I agree that isopropyl is not very good, but ethanol makes a damn good flux cleaner if used properly.
----- Original Message ----- To: "Multiple recipients of list CHIPDIR-L" <[EMAIL PROTECTED]> Sent: Friday, February 28, 2003 10:39 AM > Syd -- > > Why not let your solder supplier recommend proper flux removal procedures??? > After all, that _is_ their business. > > I am sure that you will hear of many "home" remedies for this problem. I > consider straight alcohol one of the worst. All it does is disolve and > dilute the flux and smear it all over the board. It only makes the mess > worse. > > I have, for many years, used Kester-44 solder exclusively with excellent > results. Kester recommends that defluxing that solder is "optional". It > seems that in your special case it may be necessary. Kester then recommends > their "Bio-Kleen Sopanifier Concentrate" for de-fluxing K-44. My procedure > for batch work is then to mix Bio-Kleen with (very) hot water at a > concentration of about 2-4% by volume in a Pyrex dish of adaquate volume. > The boards are allowed to soak for about 15 minutes and then lightly > scribbed with a bristle brush (I use an ordinary paint brush with the > bristles cut down to about 1" long to make them a bit stiffer) and then > allowed to soak another 15 minutes. After this the flux remover is poured > off and the boards are rinsed for 10-15 minutes in hot running water and > then oven dried at about 180 to 200 deg F. (Be sure that all parts on the > boards will withstand this temperature.) > > I wear latex rubber gloves throughout this procedure. > > I have talked to assembly houses that use Bio-Kleen in commercial > dish-washers for volume cleaning. > > Oh, a tip - Kester will happily ship you a quart sample of Bio-Kleen at no > charge, but they will ask you to pay the shipping. Be _very_ careful, > shipping will be via Fed Ex, special handling for hazardous materials, and > will set you back about $95.00. I am now looking for a local supplier of > Kester materials. > > Best wishes, Bob Smith > > > > > > > --- Avoid computer viruses, Practice safe hex --- > > -- Specializing in small, cost effective > embedded control systems -- > > http://www.smithmachineworks.com/embedprod.html > > > Robert L. (Bob) Smith > Smith Machine Works, Inc. > 9900 Lumlay Road > Richmond, VA 23236 804/745-1065 > > [EMAIL PROTECTED] > > ----- Original Message ----- > To: "Multiple recipients of list CHIPDIR-L" <[EMAIL PROTECTED]> > Sent: Friday, February 28, 2003 8:09 AM > > > > I am working on a high voltage shunt regulator design where contamination > on > > the circuit board is causing problems. What is the best way to scrub or > > rinse all or most of the ionic contamination off a circuit board? I > usually > > use denatured alcohol to remove flux residue, but that is not good enough > in > > this case. Any suggestions or wisdom would be much appreciated. > > > > Here is a link to the Data Sheet on the little project: > > www.logwell.com/products/Codatron.PDF > > > > Syd H. Levine > > AnaLog Services, Inc. > > Phone: 270-276-5671 > > Telefax: 270-276-5588 > > E-mail: [EMAIL PROTECTED] > > URL: www.logwell.com > > > > > > -- > > Author: Syd Levine \(AnaLog\) > > INET: [EMAIL PROTECTED] > > > > Fat City Network Services -- 858-538-5051 http://www.fatcity.com > > San Diego, California -- Mailing list and web hosting services > > --------------------------------------------------------------------- > > To REMOVE yourself from this mailing list, send an E-Mail message > > to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in > > the message BODY, include a line containing: UNSUB CHIPDIR-L > > (or the name of mailing list you want to be removed from). You may > > also send the HELP command for other information (like subscribing). > > > > > > -- > Author: Robert Smith > INET: [EMAIL PROTECTED] > > Fat City Network Services -- 858-538-5051 http://www.fatcity.com > San Diego, California -- Mailing list and web hosting services > --------------------------------------------------------------------- > To REMOVE yourself from this mailing list, send an E-Mail message > to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in > the message BODY, include a line containing: UNSUB CHIPDIR-L > (or the name of mailing list you want to be removed from). You may > also send the HELP command for other information (like subscribing). > -- Author: Syd Levine \(AnaLog\) INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB CHIPDIR-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
