Electronics Forum | Mon Sep 24 11:12:56 EDT 2001 | nwyatt
Hi. We are currently using an unconventional method to rework a micro BGA - removing component with hot air, fluxing the area, placing the part with pick and place, then reflowing it in the oven. The reason we are doing it this way and not with a r
Electronics Forum | Tue Sep 25 12:49:58 EDT 2001 | Hussman
Been there - done that. Makes a mess on that 2nd reflow process- doesn't it!?!?!? This is caused by design. If the open via is located in the land area, it will flow thru the via and cause pumps on the opposite side. You can have your vias filled
Electronics Forum | Wed Sep 26 11:54:02 EDT 2001 | Stefan
John, you mention yourself that this problem is component related. Is the 1206 presented out of a plastic tape?. The tape could be more slippery than the paper tape and the cover tape may pull the tape out of position. I am not familiar with the Juk
Electronics Forum | Thu Sep 27 10:20:46 EDT 2001 | John S
The feeders on the Juki 750 machines have about 0.060" slop in the x-axis. Which allows the machine to try to pick up the part on the edge,inverting it. With the auto-correct feature enabled, the machine locates the feeder pocket based on its pick
Electronics Forum | Wed Sep 26 16:31:30 EDT 2001 | davef
Wudduya mean ya can�t replace that ol� John Trieber? We agree. * Waverider thingies are best used to set-up process and in machine start-up. * Monitoring product characteristics is expensive, gives little information, and is so sloooow. [Plus we tu
Electronics Forum | Tue Oct 02 12:56:41 EDT 2001 | Scott B
We have come across this where the operator was using thin gauge solder wire (more suited to fine pitch SMT soldering) to form large solder fillets (power connections or sheild cans). We found that the operator was feeding large amounts of solder wir
Electronics Forum | Tue Oct 02 18:49:01 EDT 2001 | Suresh Balas
Hi I am developing an application that is used for data collection from the shop floor and would like to provide the technicians with a CAD viewer that will help them locate and repair components faster. 1) I would like to know what the industry sta
Electronics Forum | Wed Oct 03 09:56:51 EDT 2001 | Claude Tremblay
Hello everyone We have a QFP-308 (0.20" pitch)on a board and we have a lot of opens after reflow. We checked our profil by installing thermocouples on the pads of the component and everythings seems OK. We checked the coplanarity of the leads and it
Electronics Forum | Wed Oct 03 12:04:55 EDT 2001 | slthomas
When we found this to be a problem with some QFP 100's (.020" pitch, and our first experience with fine pitch - 48 of them on a 2-up panel), we saw that the solder was running up the leads during reflow and staying there, leaving the fillets thin or
Electronics Forum | Wed Oct 03 17:06:43 EDT 2001 | davef
Yes, moisture entrapment causes solder shorts 80% of the time. Cracks occur bottom side of the BGA. Use an acoustic microscope to find the cracks. So, what makes you think your BGA are blowing-off steam? I posted a vid on SMTnet that showed the b
