Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.

No Clean Solder/WS Flux



No Clean Solder/WS Flux | 23 October, 2002

Hello everyone. Can someone please tell me if there are problems using No Clean solder for SMT and then using WS Flux with our Wave process? We are aquaeous cleaning after...but are there other cross-contamination issues? THANKS!!!

reply »

Kevin Facinelli


No Clean Solder/WS Flux | 24 October, 2002

The big problem we saw was the appearance of the solder joint after the water wash process. We saw the joints turn white through the absorption of moisture. Looked real bad but still functioned. I would stick with using only one of the processes and not mixing. I am a strong proponent of the W/S solder paste and fluxes....

No Clean means no clean...or at the least very, very hard to clean in my experience.

Good luck,


reply »



No Clean Solder/WS Flux | 25 October, 2002


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.


reply »


No Clean Solder/WS Flux | 28 October, 2002

Good Morning,

I think that the use of No clean at SMT and the use of WS at wave is counter productive. For the most part, you will get better results using WS at SMT. If you use No Clean, and then are forced to run this thought a water wash as a requirement of the WS at wave, you will discolor the No clean flux left from the SMT process. The residues are usually harmless but an eyesore. There are some No clean formulas that are water washable and will not leave a discolored residue but at this point, I do not see why you wouldn't use a WS.

Hope this helps

Christopher Lampron

reply »



No Clean Solder/WS Flux | 29 October, 2002

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

reply »

Software for SMT

 Reflow System