Electronics Forum | Tue May 25 11:37:50 EDT 2010 | davef
Where on the assembly is the dewetting occurring? Factors that influence dewetting usually involve non-ionic contamination such as: * Residues from board manufacture including silicone surfactants from solder resist & HASL rinse contamination * Comp
Electronics Forum | Thu Dec 06 19:46:08 EST 2001 | davef
First, we�re assuming that we�re talking hot air solder leveled [HASL] bare boards, eh? Consider using A-600 - Acceptability of Printed Boards as the basis for discussing the bare board problems. It is the bare board analog of A-610 - Acceptability
Electronics Forum | Thu Apr 20 02:27:11 EDT 2017 | pavel_murtishev
Mile, Please tell me more about your soldering process: - Are soldering process parameters the same for all three pins? - Is unsoldered pin connected to thermal heavy copper polygon? - What is your board surface finish? HASL? - Sn/Pb or LF process?
Electronics Forum | Wed Mar 12 15:26:46 EDT 2014 | dan_ems
Hello, in my SMT process I have some problems with the solderability (look like dewetting) on a PCB with finish HASL Lead Free with a composition that is melt at 230 degree Celsius. My oven is with vapor phase and the peak temperature is 230 degre
Electronics Forum | Thu Oct 27 08:27:57 EDT 2005 | Adam
Hi We are trying to solder a a contact whose base material is stainless steel, this is then nickel striked with a gold plating of upto 3 microns. We are trying to hand solder this to a standard 1.6 FR4 PCB with a HASL finish. We are seeing problems
Electronics Forum | Sun Nov 24 09:54:24 EST 2002 | davef
On a HASL board that has poor wetting on the pad, consider looking further downstream in the process than your assembly shop. For instance, take a look at the bare boards. Look for solder mask bleed onto the pads. This will show-up on the outside
Electronics Forum | Wed May 14 12:42:16 EDT 2008 | rgduval
Dave, Realized I didn't respond to one of your questions. We pasted and reflowed one board, with no components. This board exhibited extreme dewetting on all pads. The board was LF-HASL, and the paste was Qualitek (which we've used for approximat
Electronics Forum | Mon Jun 14 10:23:53 EDT 2010 | pcrane
I have CCA that has a SN100C HASL coating that I am wave soldering with SbPb. I have mounting pad areas on the CCA that are masked with a pallet during reflow so they are not exposed to the solder. The mounting pads are turning gray in some areas of
Electronics Forum | Tue Jun 06 11:47:33 EDT 2017 | stevezeva
Hi Zac, was that board finished with tin/lead HASL or leadfree/HASL? Also what type of flux were you using? Just because a board is fresh out of sealed packaging doesn't necessarily mean that it's going to solder well. The picture that I've attached
Electronics Forum | Fri Dec 10 12:24:46 EST 2010 | davef
Causes of dewetting in conformal coating. Factors that influence dewetting usually involve non-ionic contamination such as: * Residues from board manufacture including silicone surfactants from solder resist & HASL rinse contamination * Component res
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