Electronics Forum | Fri Apr 21 18:43:23 EDT 2006 | SD
Sorry, I have not read the article. However, I do have five years experience constantly tweaking an AOI system that ran ONE product! The strength of the machine was solder inspection. The biggest problem was component color variation and shadowing
Electronics Forum | Fri Aug 15 10:23:56 EDT 2008 | ck_the_flip
Ovens, and any other process for that matter, will ALWAYS vary. It's called process variation. I do Cpk (process capability) on my ovens. I track time-above-liquidus and peak temperatures. Statistics will validate how repeatable your oven is.
Electronics Forum | Mon Nov 26 14:49:20 EST 2001 | mparker
1. The formula for cubic area (LxWxH) applies to get the expected volume target value. Caution- do not assume the pad surface square are is correct for the part. Do consider the footprint of the device beign placed and its solder requirements to cre
Electronics Forum | Wed Jan 14 14:36:29 EST 1998 | Mike Cox
Your questions would require volumes of information to answer completely. This is a readers digest version to help you get started volumes Don't rely on inspection as a process indicator of your quality and defect levels. Unfortunately Inspectio
Electronics Forum | Thu Aug 21 16:58:25 EDT 2003 | justin
With a eutectic ball, you'll see about a 50% collapse. This negates that .008" issue you're referring to. With a high temp ball, you don't enjoy the same freedom regarding ball collapse. Dave is correct, though. We recently got IBM to sign up to
Electronics Forum | Tue Apr 27 16:00:19 EDT 2010 | scottp
In a nutshell, Cp is a measure of your process variation compared to your spec limits and Cpk is measure of both variation and how well your process is centered within your spec limits. Cp = (USL-LSL)/6*sigma where USL=upper spec limit LSL=lo
Electronics Forum | Wed May 20 10:00:00 EDT 1998 | EFData
The quick frame does work well with the DEK 265, but we feel that tensioning is user dependent and introduces variation into the process on an operator to operator basis. Also, because tensioning occurs only on two sides (instead of four) this also i
Electronics Forum | Tue Jan 11 10:01:30 EST 2000 | Wolfgang Busko
Hi Pat, we had white tin boards laying around for about 10 month with no extra protection than the plastic bag that they were shipped in. Never thought of using them for there was a relayout planned to fix some serious bugs. But that�s life, relayo
Electronics Forum | Mon Dec 06 13:32:47 EST 1999 | Bob Smith
CPk is a measure of the process variance with respect to the acceptable upper and lower limits. In your case it would be the accuracy of placement. The exact position of a chip ideally would be dead centre on the pads however in real life that positi
Electronics Forum | Tue Mar 15 12:20:47 EST 2005 | Material Man
The use of nitrogen in lead free wave solder operations is primarily used to reduce or even eliminate drossing of the solder, thus improving solder yield. The higher priced lead free solder makeup (Cu, Ag) make this a more economical proces than the
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