Electronics Forum | Tue Sep 25 14:08:59 EDT 2001 | davef
Oooo, the solder on the pad and PGA ball is flowing during reflow down the via to the secondary side? Why didn�t you say so?? ;-) Why would you expect that gravity and capillary action wouldn�t force solder to flow down the solder plated via to the
Electronics Forum | Fri Sep 10 12:09:02 EDT 1999 | Earl Moon
| | | hi, i m college student. i m currently doing my Final year project in PCB drilling. the main task is to design auto feeder which allign the PCB properly in position before drilling take place. the close tolerance becomes a big problem to the pr
Electronics Forum | Sun Sep 12 08:20:04 EDT 1999 | se
| | | | hi, i m college student. i m currently doing my Final year project in PCB drilling. the main task is to design auto feeder which allign the PCB properly in position before drilling take place. the close tolerance becomes a big problem to the
Electronics Forum | Tue Jan 12 15:11:20 EST 1999 | Earl Moon
| | I have an Electrovert UPK 660c fitted with IR preheats top and bottom. We assemble a large range of multilayer backplanes and I was wondering if there are any advantages in changing to convection preheats.Has anybody got any views on the subject.
Electronics Forum | Mon Sep 14 17:39:37 EDT 1998 | Steve A
| I am running composite fixtures on my wave solder machine and after about 500 passes each (1 month)they are showing serious signs of wear in that the composite surface is bubbling up and glass fibers are also starting to show. | The problem here
Electronics Forum | Tue Jun 09 07:35:23 EDT 1998 | Steve Gregory
Hi there Gary, Your solder ball problem is very similar the problem I experienced, but I was using a water soluble paste at the time. It started by inspectors telling me that they were seeing cold solder on some SIMM's that we had built regularly. W
Electronics Forum | Wed Feb 26 21:38:08 EST 2003 | jonfox
1. First and foremost is paste alignment. If you start out of the gates with a bad paste/pad relationship, it will be nothing but problems down the line. AOI is not required, but dial in the alignment, QC if necessary, then introduce the boards to
Electronics Forum | Mon Oct 30 16:00:30 EST 2000 | Finepitch Services
Sal, I kind of assume you have paste there to start with... Because sometimes the edge components do not have paste applied caused by the bottom support in the screen printer etc. And if that is the case for one direction, the other direction applie
Electronics Forum | Mon Feb 05 20:43:27 EST 2001 | davef
1 Solder on gold fingers comes from: 1a About 70 % of the time it's caused by poor cleaning of screen printer, staging area (table), conveyor, reflow oven chain or belt, and keeping boards separate from cleaning process 1b After loading paste onto
Electronics Forum | Fri Mar 23 14:13:20 EST 2001 | mnaddra
RW, I have Screened Adhesive on to several different assemblies and have found that when it is possible I get a much better result than with a dot deposition process (The green strength was greatly improved), the biggest issue I ran in to was the pr
