Electronics Forum | Mon May 12 23:28:33 EDT 2003 | dehlers
To the best of my knowledge and experience the 2 % Ag component is not for embrittlement but rather to reduce gold scavenging caused by the propensity for tin to react with the gold. I have seen eutectic tin/lead actually disolve gold wire after a f
Electronics Forum | Thu May 15 15:42:33 EDT 2003 | davef
Unless you have a reason, set your top and bottom to the same temperature. Tip: Don't run dry cleaners bags through the oven. Tell us about: * Paste you intend to use. * Specifics of your oven, including length of each of the heating and cooling zo
Electronics Forum | Mon May 19 02:59:04 EDT 2003 | emeto
Hi, I can give you a few steps. 1. The solder paste. Take the profile that manifacturer gives for the paste. 2. Use termocouple to measure the tempereture. Put PCB and measure the temperature in equal terms. 3. Compare your profile to manifacturers
Electronics Forum | Mon May 19 15:39:56 EDT 2003 | pjc
Curious. Are you finding no applications support from Dima or Manncorp (if a USA Dima customer) or Kester for that matter? DIMA SMT Systems NL. B.V. Beukelsdijk 2 5753 PA Deurne Netherlands Tel: +31 493 352 752 Fax: +31 493 352 750 sales@dimasmt.nl
Electronics Forum | Thu May 15 03:14:33 EDT 2003 | Hon Choi
Dear all, Not sure if you have this experience, but we've been seeing shorts on the BGA's from a widely known supplier "i". These shorts can not be found on the X-Ray, and when we remove the BGA, the component is ok. We peeled a few BGA's off, and
Electronics Forum | Thu May 15 07:37:49 EDT 2003 | pteerink
Have seen similar circumstances a couple times. Possible causes: 1) PCB defect - remove the BGA and inspect/test the PCB for shorts. ( trace short, layer short etc ) 2) PCB defect that only shows up when the BGA is populated - a short somewhere o
Electronics Forum | Sat May 17 02:13:43 EDT 2003 | Hon Choi
Thanks all. We are using no clean, so the boards are not washed. That would eliminate the trapped water issue. We would check the PCB after dismounting the BGA, and the short would not be found. When we place another BGA on the board, the board w
Electronics Forum | Fri Sep 12 22:57:13 EDT 2003 | Dean
What is the surface finish of the PCB? Tin? Imersion Silver? What flux is used in wave solder and / or SMT? I have much experience with silver migration and tin wiskers. Both can disappear during a reqork cycle. Both can be extremely difficult
Electronics Forum | Fri May 16 08:13:26 EDT 2003 | radney
We are a mixed volume facility and we are doing our utmost to achieve 55% utilization on HSP's (UIC 4797's and 4791's) We are basing this on a world class metric. I am wondering if anyone else out there is measuring utilization, what sort of result
Electronics Forum | Mon May 19 17:17:41 EDT 2003 | JB
We currently use a Universal GDM for our glue dispensing applications, piston pumps. My question is: Have you had any problems with air getting in the dispense system that will cause missing dots? If so, how have you approached to this problem? Int
