Electronics Forum | Wed Jul 29 13:44:45 EDT 1998 | David Spilker
We are investigating alternatives to HASL finishes for more dense PWBs. OSP is not a good choice because of low solid flux and possibly long shelf life. Immersion gold is expensive and so far has been more difficult to wave solder. Has anyone had
Electronics Forum | Mon Aug 07 09:04:09 EDT 2006 | molos21
Hi everyone, I am starting to use the lead free process and I had a few wetting problems (solder did not reach top side) at the wave soldering process once the pcb had passed our smt line (one heat pass). From what I understand, I have had a problem
Electronics Forum | Mon Sep 22 15:32:20 EDT 2008 | davef
We see this fairly often. It doesn't affect solderability. Our analysis makes us think this coloration is copper. The reason copper appears on the surface may be that heat cycles increase the thinness and porosity of the immersion silver [IAg] coatin
Electronics Forum | Thu Sep 06 17:37:05 EDT 2007 | hakerem
Hi Joris - There is an excellent wave solder guide called "Take No Prisoners" that includes instructions for attacking and eliminating solder balls and preventing their recurrence: 1. Increase Dwell Time Solder balls are normally caused by too much f
Electronics Forum | Mon Dec 17 12:06:58 EST 2007 | pjc
5 Steps to Eliminate Bridges: 1. Establish (wave) Parallelism First and foremost, you must establish board-to-wave parallelism. This is the prerequisite to any wave solder process control. For an understanding of the power of this approach go to ht
Electronics Forum | Thu May 10 19:19:41 EDT 2007 | rgduval
Wayne, I haven't seen anything indicating that Gold Immersion is necessary for lead free... However, it is my companies preferred finish for lead free assemblies. We've taken this stance for the following reasons: 1. Better solder quality on th
Electronics Forum | Thu Nov 08 13:12:02 EST 2007 | russ
Annular rings are too big, it is acceptable to have shorts on the common conductors. I would be willing to say the "other" supplier may have modified the artwork as well. Good fluxing, preheat and proper immersion depth are key to eliminating short
Electronics Forum | Fri Dec 16 08:00:26 EST 2005 | jax
What you are most likely dealing with: Insufficient Pure Sn layer ( multiple causes ) Because elevated temperatures accelerate the diffusion process, the thickness of the Pure Sn layer will reduce during every thermal cycle... ( bakeing PCBs, S
Electronics Forum | Wed Jul 29 22:50:17 EDT 1998 | Dave F
| We are investigating alternatives to HASL finishes for more dense PWBs. OSP is not a good choice because of low solid flux and possibly long shelf life. Immersion gold is expensive and so far has been more difficult to wave solder. Has anyone ha
Electronics Forum | Fri Dec 16 13:31:28 EST 2005 | gpaelmo
Thanks for your response.