Electronics Forum | Mon Sep 17 03:59:52 EDT 2012 | stivais
Hi guys, We have an interesting case we haven't seen before (see the picture below) http://postimage.org/image/lu2f4ae55/ Solder balls form on unpopulated pads after reflow. 1. Reflow profile is fine. 2. Stencil thickness / paste volume is also f
Electronics Forum | Mon Sep 17 09:47:18 EDT 2012 | mbnetto
Hi, Do you want to replace the SB ou just reflow it again? Do you suspect there is some "colder solder joint" in one of the SB balls ? In my opinion you are heating the board a lot... Did you put some thermocouple on the ball to check the temperat
Electronics Forum | Mon Sep 17 13:52:56 EDT 2012 | comatose
We have an old (dinosaur, 1992 vintage) heller 988 that we use for shrinking heat shrink, curing, low temperature stuff. We need another similar oven for expanded production. Essentially any reliable, running, non-lead-free three four or five zone ov
Electronics Forum | Tue Sep 25 11:50:37 EDT 2012 | davef
Ken ... I resized your picture so that it fits on the page better. Continuing with your outgassing through the solder pads theory, how thick is the copper on the pads? I don't expect to see outgassing through pad that are a thou or more in thickness
Electronics Forum | Sun Sep 30 09:50:18 EDT 2012 | rgduval
We believe that Dave's analysis above is mostly accurate. Run a board with no components, and check for voids. We'd also like a little more information, though, to clarify. What type of component is experiencing the voiding? You describe the void
Electronics Forum | Wed Oct 03 19:28:58 EDT 2012 | rgduval
Given that you're seeing it on nearly every part, we tend to lean towards Dave's explanation. We wouldn't expect outgassing from the pad to be an issue (at least, we've never heard of it before, which doesn't, necessarily, eliminate it as a potentia
Electronics Forum | Thu Oct 25 13:33:18 EDT 2012 | cyber_wolf
Ken, The photo looks like results I have seen because the gold flash was too thick on the board. This causes a condition known as gold imbrittlement. You may want to get an analysis of the plating thickness. I'm not real experienced with immersion si
Electronics Forum | Wed Sep 19 06:42:56 EDT 2012 | ekki511
Hello alltogether we have some old assembleon mashines here in hungary. Since some days we are fighting with our Eclipse. After started if we push the ready button appear the error code : L006:Tr.over current. Does anyone know what is Tr. ? Is this
Electronics Forum | Wed Sep 19 12:27:52 EDT 2012 | tombstonesmt
Looking into possibly receiving samples of polyester masking dots for conformal coating. Our usage of polymide dots have really increased in the past months and we're always looking for a reduction in costs. The only information I've found is that po
Electronics Forum | Mon Sep 24 10:07:46 EDT 2012 | eezday
The answer, as stated above, is 3 microinch's however, it is equaly important, if not more important, to understand that the only function of the gold is to protect the surfaces beneath it. Only enough gold to cover the nickel beneath it should be u
