Electronics Forum | Wed Oct 11 09:55:10 EDT 2000 | Ian Harrison
Some boards that are populated by one of our subcontractors are getting a white powdery residue forming on them. I think it is the non clean flux and process which they are using that is causing the problem. Their process is as follows. Flux is put i
Electronics Forum | Fri Oct 13 15:16:43 EDT 2000 | Dave F
George and the others make good points. Check Les Hymes response to a similar question in 7/00 "Circuits Assembly"
Electronics Forum | Fri Oct 25 04:13:33 EDT 2002 | kcngoi
Hi, No clean mean is no need to clean. Of couse if you usin incompatibility solvent to clean, the white residue will appear. If cleaning is needed, source the suitable solvent and this always suggested by your solder paste supplier. regards
Electronics Forum | Tue Oct 29 08:41:48 EST 2002 | peterpaulmary
from my experience, no clean mean "difficult and cannot clean" Normally, you will observe white residue when cleaning it. You should study the flux in the no-clean solder cream before cleaning it. Or change no clean solder to clean type solder
Electronics Forum | Sun Jan 26 22:28:46 EST 2003 | iman
we had a project like this once. switched to using "genosolve" chemistry (US source, expensive) in conjunction with a degreaser machine, works fine if you can spend the money.
Electronics Forum | Mon Jan 27 12:02:00 EST 2003 | Mike Konrad
Dave is correct. No-clean flux + water = white residue (unless the proper chemical is mixed with the water). Additionally, no-clean flux + IPA = white residue. Many saponifiers work well as do other cleaning agents. White residue may also be a re
Electronics Forum | Fri Apr 04 10:02:20 EST 2003 | rdr
Do you reflow both sides of the boards before washing? Sometimes these white residues occur from "burnt" flux. we see this from time to time especially when using hot air and liquid flux. Russ
Electronics Forum | Mon Mar 29 11:15:58 EST 2004 | davef
Grant & JDumont: You should not have this white residue on your wave soldered connections, using VOC flux [but you know that, anyhow]. Applying too much flux is the likely cause. Other possibilities are: * flux contamination * solder contamination
Electronics Forum | Fri Apr 02 06:26:13 EST 2004 | Phil James
Take a look at the downloadable paper on the subject of "White residues" available from NPL www.npl.co.uk/ei (Downloads) By the way, we also suffer from this problem!
Electronics Forum | Fri Apr 02 12:40:59 EST 2004 | Ron Herbert
White residue can often be caused by overheating the flux. When this occurs the flux is polymerized, basically turning it into an epoxy. You can usually determine if this is the problem by taking a pencil eraser to it. If it comes off, you have overh
