Electronics Forum | Tue May 31 09:40:23 EDT 2005 | mattkehoe
We have some boards that exhibit poor solder wetting when reflowed. Nothing fancy, smallest pitch size .050. See photo's at http://www.sipad.net/SnPbwetting.htm Is this ; Contamination on the HASL finish? Insufficient solder,not enough to cover pad
Electronics Forum | Tue Jun 28 13:04:08 EDT 2005 | slthomas
Are you saying that increasing the frequency of cleaning to every 3 boards *reduced* bridging, or that it's just something you tried? I don't understand why that would help(in my experience it has reduced "insufficient solder" conditions but not brid
Electronics Forum | Wed Oct 19 13:32:12 EDT 2005 | shk5678
I have a couple of customers I showed this to and they were impressed with the capability but didn't know the price yet. Reason being was the control of the amount of paste applied to the pads could be adjusted. They both said they had problems with
Electronics Forum | Fri Mar 03 14:40:22 EST 2006 | amol_kane
i think a more important issue here would be the reduction ratio. as LF solders have a higher surface tension, they do not flow as well as their leaded counterparts. therefore the stencil design may have to be changed (hence a new stencil) if the red
Electronics Forum | Thu Sep 07 10:32:12 EDT 2006 | slthomas
Is the solder reflowing on the pad but not wicking up the lead, or does there appear to be insufficient solder to wet both, or is it not reflowing at all, or.....? Have you verified your profile? What is the condition of your paste (expiration date,
Electronics Forum | Mon Oct 09 10:58:26 EDT 2006 | Matt Smith
Over the past several months we have experienced intermittent problems with wave solder voids on PCBs coated with OSP. We suspect variation in the OSP application process, or oxidation of the surface due to insufficient or degraded OSP. Is there a me
Electronics Forum | Tue Nov 07 14:34:04 EST 2006 | jeffm
We are using Kester Type R520A, Alloy SN96.5/A63.0/CU.5 paste which is applied using an MPM Accuflex machine. Our plant Humidity is 38 degrees. We are seeing insufficient paste post stencil on fine pitch parts. Could this be an environment issue? In
Electronics Forum | Wed Jan 17 10:14:37 EST 2007 | slthomas
2-3mm would seem close enough to affect the air flow and I was thinking it could be displacing the qfn. However, if you ran a failed board back through reflow and it was functional after that, I'd put my money on insufficient reflow. I suppose it's
Electronics Forum | Tue Jan 16 20:44:07 EST 2007 | davef
Bridging Causes: Insufficient flux, Excessive pre-heat, High conveyor speed, Solder contamination Look here: * http://www.smtnet.com/library/files/upload/Reflow%20Wave%20Poster.pdf * http://smt.pennnet.com/Articles/Article_Display.cfm?Section=Archi
Electronics Forum | Tue Jan 23 07:18:24 EST 2007 | cyber_wolf
Hi, We have a UP2000 with grid lok installed on it. We run several assemblies that have component pads close the edge of the board. The side clamps hold the stencil up off the board and we are either getting insufficients or excessive solder paste in
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