Electronics Forum | Fri Jun 15 11:22:14 EDT 2012 | hegemon
Good info above from davef Solder pot contamination seems likely, are you using any dross reducers or additives that might be reacting with this particluar batch of PWBs? 'hege
Electronics Forum | Thu Jun 21 23:00:16 EDT 2012 | davef
It's possible that if the nickel on your board was skip plated by your fab that you would get the symptoms that you describe.
Electronics Forum | Fri Jun 22 07:16:37 EDT 2012 | brettrenishaw
Spray fluxing yes but have checked the uniformity by using a fluxometer. Also have put boards through with only flux and preheat. no wave up to see if the carrier is being burnt off. I will look into the skip plating issue. Thanks again
Electronics Forum | Fri Jun 22 06:31:08 EDT 2012 | grahamcooper22
Are you spray fluxing ? If so, check that you are getting flux onto the whole pcb uniformly.... That BLT flux is a water based material, are you getting rid of all the water in the preheat before you get to the wave ( can you hear any spitting as t
Electronics Forum | Wed Jun 13 16:51:26 EDT 2012 | davef
Sorry, but I don't have a quick and easy answer. Before jumping the 'black pad shark,' tell us more about your boards ... * Is the gold still on the pads after soldering? * Can you make the pads take solder using a soldering iron? * Does this happen
Electronics Forum | Thu Jun 14 04:24:32 EDT 2012 | brettrenishaw
Yes pads are still gold after the wave soldering process even if you wave solder a pcb several times. I have tried soldering using an iron and the solder takes to the pad as you would expect. This happens on all boards of this type and all boards are
Electronics Forum | Mon Jun 18 04:21:22 EDT 2012 | brettrenishaw
Measured the pot temprature independantly from the software (268C/514F from moving wave). We are using Dross Inhibiter Tin/P Regenerator from BLT. Monthly sample checks are carried out on the solder bath and are all within limits. It will be hard to
Electronics Forum | Thu Jun 14 15:29:29 EDT 2012 | davef
That you can get good solder flow when hand soldering seems to indicate that the temperature of your solder pot is too low. Still, I'm uneasy that you see gold on the pads after passing the board across the solder pot. Gold is so thin with ENIG. So
Electronics Forum | Tue Mar 01 18:19:20 EST 2005 | russ
Indium NC SMQ92J for both lead and unleaded
Electronics Forum | Wed May 07 07:56:51 EDT 2008 | ck_the_flip
We go RoHS. I learned in a seminar that one can ingest Bismuth and not die.