Electronics Forum | Thu May 10 15:32:45 EDT 2012 | 14367
We are having a lot of tomb stoning with this no clean solder paste. It's limited to larger, complex boards, affecting 0603 ferrite beads, capacitors and SOT23s. It was suggested that paste removed from a stencil should not be put back in it's origin
Electronics Forum | Tue May 22 11:08:12 EDT 2012 | patrickbruneel
It sound like this connector is a serious head sink which can be solved with more preheat or slower conveyer speed. It might also be a combination of the heat sinking capability of the connector together with encapsulated flux underneath the connecto
Electronics Forum | Wed May 23 11:57:00 EDT 2012 | patrickbruneel
Since you have an alcohol based flux one more thing you can try to eliminate flux encapsulation under the connector. Is flux a board and remove when fluxed. Let the board sit for an hour to assure all solvents are evaporated and place the board in th
Electronics Forum | Tue May 22 11:38:04 EDT 2012 | naynayno
I am looking for IPC or other published standards that specify cleanliness levels for: 1) solder paste stencils 2) selective solder pallets When we cleaned PCB's we used a limit of 4 M-ohms. Now that we have transitioned to No-Clean, I am wonderi
Electronics Forum | Thu Jun 07 05:11:42 EDT 2012 | cp38260
Hi, I have pcbs (Duroid/RT 5880) with raw copper, soldered in vapour-phase chamber at 230 degrees Celsius. During soldering, copper gets tarnished. Cleaning with Vigon A250 removes the tarnished layer. Indeed, in the VigonA250 techn. datasheet it is
Electronics Forum | Wed Jun 20 08:46:15 EDT 2012 | jdengler
Hello all, We have a customer requesting the use of Sn95/Sb5. Of course they are in a hurry and I have not found any in stock. I need solder paste and cored wire. We can use water soluble or low residue (no-clean) flux. Anyone have a lead on a s
Electronics Forum | Thu Jun 28 09:57:50 EDT 2012 | mosborne1
blow holes and via holes are almost always caused by moisture and in PTH they could be moisture and improper drilled holes. If you are seeing solder balls next to the parts than I would say you have a reflow profile problem. Are you using any kind of
Electronics Forum | Thu Jun 28 16:02:05 EDT 2012 | allwave
We had a similar problem with foam in our inline cleaner (TD). The problem were the solder paste flux residues. Boards went straight from SMT to Wave process and then washed. Anyway we changed the solder paste and problem solved. Are you using saponi
Electronics Forum | Wed Jul 04 12:18:14 EDT 2012 | davef
Phil is correct in his description of proper rework technique. Possible explanations of the reason for popping of your BGA are: * Thermal cycling of components cause them to flex on a different point in the cycle that the board possibly resulting in
Electronics Forum | Sat Aug 25 23:01:45 EDT 2012 | ssridhar
Hello jdumont, I think the spheres are leaning as there is not enough meat under the spheres. In ceramic BGA devices there is a solder fillet which is generally a solder paste which is used to give the device some height before balling it. This heig