Electronics Forum | Fri Sep 10 09:39:32 EDT 2004 | Bryan Sherh
Dears, I've a board with OSP surface finish,and I planned to print solder paste on the test pad for easy ICT, because the probe can't reach the OSP covered pad.But to my surprise,after reflow there's much flux residue on top of test pad(or solder) an
Electronics Forum | Tue Jan 03 17:36:49 EST 2006 | MikeF
If you know you have cleaned any flux residues that were under there you could consider a bead of an electronic grade RTV, such as RTV3145. If you trap any uncleaned residues under there you could have long term reliability problems. But, like Dave
Electronics Forum | Thu Oct 05 12:14:15 EDT 2006 | Mario Scalzo, SMT CPE
Good afternoon! We have had great luck with semi-aqueous cleaners from Kyzen and Zestron, and normally recommend both of them. They both have great labs and would gladly offer their input on he cleaning of the flux residue. We make sure that these
Electronics Forum | Mon Sep 08 14:29:04 EDT 2008 | davef
�Another direct measurement to determine resistivity values (i.e. of remaining no-clean residues) can be performed through impedance spectroscopy. The surface resistance underneath chip resistors and capacitors can be determined to show the improveme
Electronics Forum | Tue Apr 28 21:48:50 EDT 2009 | davef
Confirm the source of the issue. Run a coalescence test on both lots of paste. A simple coalescence test can quickly determine the condition of solder paste after prolonged use. Simply print a small disk [around 4-5mm diameter and 0.2mm thick - a bu
Electronics Forum | Mon Apr 23 14:05:07 EDT 2007 | Cmiller
Dave, we have the same issue running a new bare board through the oven with no paste. If there is an imcompatibility with our flux would it still manifest itself when there is not flux? Im sure there is some residual flux in the oven all the time. We
Electronics Forum | Wed May 27 15:09:30 EDT 1998 | Dave F
| | | | We recently made the switch to no-clean and the wurface mount is turning out beautifully. However, the wave solder process continues to put up a fight; we are getting a white residue on the surface of the PCB. The residue is not locali
Electronics Forum | Fri Jun 14 14:19:17 EDT 2002 | davef
Consider: * 007 is a no-clean flux. Some no-cleans you can clean, some you can�t. You may be able to use a saponifier & surficant to clean the residue. Check with your flux supplier for recommendations. * 320�C is higher than the 315�C peak for th
Electronics Forum | Thu Jan 28 08:58:10 EST 1999 | Peet
| | i am working with the noclean process and getting white residues on the bottomside of the board probably due to the | | wave soldering flux.i am using a no-clean solder paste and a noclean wave solder flux.The boards passed the accelerated tempe
Electronics Forum | Sun Jul 29 09:22:54 EDT 2001 | davef
Tough to say. The residues from fluxes vary according to the suppliers' forulations. Consider: * Talking to your supplier. * Running life cycle tests.
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