Electronics Forum | Fri Feb 19 02:11:11 EST 1999 | Pete Sorenson
| During inspection and test we find leads which do not get soldered. Some are because of insufficient paste, but with others everything looks right. This will only happen on 1 to 2 pins, and it is not isolated to a specific type of ic or location o
Electronics Forum | Fri Jul 30 16:02:49 EDT 1999 | Earl Moon
| | I received a request from customer to assemble ceramic substrate (alumina oxide)that printed with a low temperature Copper thick film conductor (the overglaze layer is polymer). The Copper pads are exposed without any coating. | | This ceramic su
Electronics Forum | Wed Jul 28 20:14:22 EDT 1999 | Dave F
| While inspecting incoming PCBs we detected around all plated-through-holes (only there and all in the same place) some halfmoonshaped light rings that match obviously only with the pink ring symptom shown in the IPC-A-600 chapter 2.5.2.. That would
Electronics Forum | Fri Oct 18 06:33:28 EDT 2002 | johnw
Here's one for you lot, dos anyone have a method or a vendor that can clean the ball's of BGA's of oxides to bring them back to 'new' conditions ? I've got a bathc of components that are fairly old and I get some issues with soldering them which I b
Electronics Forum | Fri Oct 18 07:14:51 EDT 2002 | cyber_wolf
Have you tried using a paste with a more aggressive flux? Our main paste is Indium, but whenever we run into oxidized parts or have soldering problems due to oxidation on pads we use an older Alpha WS paste called WS609. The drawback of this paste is
Electronics Forum | Thu Jul 31 15:41:23 EDT 2003 | davef
Q: Could any of you guys tell me what exactly is this greenish thing ? A: No, but is not copper oxide. Copper oxide is brown, the color of a penny [here in the US] or an untreated copper laminated trace on a board. Many copper salts are greenish in
Electronics Forum | Thu May 05 09:17:58 EDT 2005 | jimmiem
I tried soldering to several of the black pads and was successful, the solder stuck with no hesitation. so i guess this is not truly "black pad"? would that be a correct statement? What causes this blackening that looks like oxidation under the mic
Electronics Forum | Thu Jul 14 19:12:40 EDT 2005 | sync40
Hi. In the past years I had made dozens of PCBs but now I am trying to get a professional finishing on them. The main problem is oxidation of the copper traces. Basically I use the silkscreen method to make the pattern in both layers and then etch. L
Electronics Forum | Mon Jan 07 12:12:55 EST 2008 | ck_the_flip
Another thing I'm curious about. What is the "functional purpose" of soldering stainless? Solder coatings generally prevent oxidation on surfaces, but why would somebody solder STAINLESS? Stainless, by nature, is resistant to rust, and hence, oxid
Electronics Forum | Fri May 23 23:47:46 EDT 2008 | dint46
Wayne; Several things. 1.check the vendors and see what black oxide they are using are they the same ? It might be that. 2.You should bake your pcbs before the thermal stress is applied. To remove moisture. At your shop. The proce
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