Electronics Forum | Fri Apr 09 20:47:36 EDT 2010 | 89jeong
I think the oxidation on the pad happens easily but do not on Au plated pad.The reason may be caused by improper cleaning or Au plating thickness in plating process. But,before suspecting the pcb board, you need to check your process or used material
Electronics Forum | Wed Apr 14 10:24:17 EDT 2010 | fönsi
Hello Does somebody of you have some experiences with ultrasonic detectors in SMT-Production? Is it possible to test quality of solder joints by using a ultrasonic detector similar to non destrucitve crack inspection tests? Is there a manufacturer fo
Electronics Forum | Wed Apr 14 14:51:10 EDT 2010 | jgalarza
After checking some of our stencil data for the correct aspect ratio I found that a few are wrong. I would like to change them from 5mil thk to 4mil thk but do not know how much paste volume I need to keep. We are using 0201,0402, and BGA with 0.80 p
Electronics Forum | Thu Apr 15 10:05:26 EDT 2010 | davef
Why not use the same paste volume as you currently use? Alternately, although we haven't used it in a while, doesn't IPC have a very nice paste volume, aperture calculator that could be used for this? Or is it just a pad size calculator used for
Electronics Forum | Thu Oct 28 15:53:27 EDT 2010 | dwonch
Ok, just to put closure on things I figured I should post the conclusion of this whole ordeal. We've acquired a new BGA rework station that allows us to get away without tenting our vias under the BGAs. This allowed us to change our PCB spec to rem
Electronics Forum | Thu Apr 15 10:09:55 EDT 2010 | davef
Dross formation rates for SnCu and SAC are roughly 2.5 times the rate for SnPb (Hwang et al., 2004) Methods for reducing dross are: * Lower pot temperature * Run pump speed slower and only when soldering * Check solder contaminants to BS219, ASTM
Electronics Forum | Thu Apr 22 09:57:11 EDT 2010 | davef
Ralph Woodgate is the 'god of wave soldering process control.' We believe he is now retired, but in olden times his presentations at SMTA meetings were 'DO NOT MISS.' We imagine you can find his books on the used book market. Look here: http://use
Electronics Forum | Thu Apr 15 14:09:48 EDT 2010 | richardli
We found stains on the boards come out of reflow oven. The board itself color changed to yellowish from white . We understand discolor soldermask due to high temperature. This can be acceptable by our customer not the stains. The stains look like wa
Electronics Forum | Fri Apr 16 13:22:48 EDT 2010 | stepheniii
Have you tried running a few bare boards through the oven? If there is no flux on them and you still get the "stains" then I think you can eliminate the flux as the cuprit. And I've been told that white is the second most difficult solder mask colou
Electronics Forum | Fri Apr 16 12:23:40 EDT 2010 | shawnvike
We are looking at buying a new (or used) oven for low-mid volume Pb-free production. I have looked at the smaller Hellers, BTU, vitronics, etc. and I am also looking at the Manncorp CR-6000. I want at elast 5 zones, top and bottom, air (no N2) pi
