Electronics Forum | Thu Sep 27 17:25:33 EDT 2007 | chef
The short answer is immediately after reflow the problem occurs. To be more exact, what you are describing is not "rust". Rust occurs in iron. The oxidation that occurs in Tin-Lead has been sometimes called "white rust". Either way, oxidation occur
Electronics Forum | Wed Oct 10 08:01:28 EDT 2007 | ck_the_flip
We use Indium 1074-EXR on ERSA, and it's performed miracles on our yields. Spot soldering, like wave, is all about fundamentals. Put just enough flux, preheat to prevent thermal shock and activate the flux, and then solder with enough dwell time to
Electronics Forum | Wed Mar 12 11:41:41 EDT 2008 | gregoryyork
Blimey just seen the picture that is bad. You could try to dissolve some of the residue/gunge in IPA if it is flux residue it should readily dissolve if it is resist issue then only portions will dissolve leaving a white powder which is Talc If you
Electronics Forum | Wed Mar 26 09:32:46 EDT 2008 | nibirta
well i do not know if u fixed this problem already. But i cand share form my experience some info with u. We used a vigon A200 solution for such an application. the cleaner is good. But...it gives u troubles depending on the quantity of flux. It can
Electronics Forum | Thu May 15 15:02:03 EDT 2008 | ccross
We have seen this problem before. We have ALWAYS found it to be a board vendor issue. Also, we tend to see it more during the summer months. Our solution has been to bake our PCBs @ 50 deg C for 1 hr prior to use. We use immersion white tin board fin
Electronics Forum | Sat May 17 09:12:50 EDT 2008 | davef
Lead-free means expensive tin. Tin is an excellent solvent. So, metal parts in contact with molten tin must be expensive enough to resist that nature of tin. To learn more about this: * Search the fine SMTnet Archives * Look here: "Liquid Tin Corrosi
Electronics Forum | Mon Oct 20 17:03:05 EDT 2008 | davef
Josh From looking at your pix, we don't have a clue. [And we're going down to the nurse's station to get our eye checked because we don't black bubkus.] More than anything else the: * White on the pads could be solder * Copper-penny brown on the pad
Electronics Forum | Wed Nov 26 13:31:40 EST 2008 | stepheniii
I don't know why they use it. I just know I read a TI white paper that said the problem wasn't their fault even though they knew that paladium made the parts hard to solder. And once when I started a new job one of the guys said that the owner had
Electronics Forum | Tue Mar 03 09:54:11 EST 2009 | dwelch123
If your using regular 63/37 Sn/Pb solder there are alot of other metals such as Antimony,Nickel,Iron,Cadmium,Aluminum,Copper,Gold,Bismuth,to name a few. But you need a certain amount of these metals for proper solder composition. Regarding the Antimo
Electronics Forum | Tue Nov 24 19:07:12 EST 2009 | gregoryyork
I agree Patrick many people blame the assembly fluxes when it is some other hygroscopic chemistry left on the bare PCB such as surfactents from the HASL process these will do exactly what the guy reported in his post fail then cool down and pass ever
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