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 | Sun May 21 05:54:04 EDT 2000 | Sal
Currently manufacturing double-sided PCMCIA cards with a nickel/gold finish, which are 0.0235thou in thickness, using surface mount carriers. Problem we are seeing is when building the densely populated side on the second pass we are seeing lifting o
Electronics Forum | Thu Dec 16 16:46:47 EST 1999 | Mike Naddra
Steve , I use a general set of guidlines when developing reflow profiles: Ramp rate to 140 deg C - 50-60 seconds Time at preheat (140-160 deg C) - 90-120 sec Time above liquidous (183 deg C) - 45-90 sec Time at peak (215-225 deg C) - 9-12 sec peak t
Electronics Forum | Wed Aug 25 16:42:32 EDT 1999 | Dave
| | | | | | Could use a little help here. Can anyone clarify to me the cause and fix of chip caps/resistors tombstoning following reflow? | | | | | | | | | | | | Any help would be appreciated. Thanks. | | | | | | | | | | | Most common reason is
Electronics Forum | Wed Jul 07 22:59:06 EDT 1999 | Dave F
| Hi! | I'm a process engineer attempting to do a capability study on our existing convection reflow oven - Heller 1500. It was recommended by an independent consultant to do at the very least, load testing, process ready testing, and board uniformi
Electronics Forum | Fri Apr 16 11:07:53 EDT 1999 | Vic Lau
| | We process both tin/lead plated boards and gold plated boards in our surface mount group. I have used Sn62/Pb36/Ag2 solder paste on all gold plated boards to help prevent gold scavaging. To reduce the amount of different solder pastes we have t
Electronics Forum | Tue May 26 14:42:55 EDT 1998 | Justin Medernach
| We currently bake plastic SMT parts in accordance with the IPC guidelines for moisture sensitive parts. Because we have double-sided boards that are subjected to either an aqueous or semi-aqueous cleaning process, we do a 24 hour bake at 125 deg.
Electronics Forum | Fri Aug 16 10:00:03 EDT 2002 | davef
You have a very bad situation. It�s tough for the gas, flux material, er whatever to escape when the BGA is sitting on top of it and the blind via is blocking it from the other side. Obviously the vias should have been: * Placed on the edge of the
Electronics Forum | Thu Aug 21 21:05:39 EDT 2003 | Tom B
Dan, We, do alot of double reflow. Your right we typically see alot of the standards components, SOT's, SOIC's, Chip stuff. The largest we do with out adding epoxy is some 32pin PLCC's. We have several assemblies were were doing PLCC44's, Sockets
Electronics Forum | Thu Jun 24 14:34:13 EDT 2004 | tjensen
There are many factors that can lead to solder balls. Since you have just recently seen this start to occur, it is obvious something has changed in the product or your process. Since we don't have a lot of details about your process, I would sugges
