Electronics Forum | Wed May 21 12:55:35 EDT 2003 | Zhenya
Several things for your reference: 1. Starting with data collection: - Have you done a measle chart to illustrate the pattern of the defect? - Have you checked the corelation between shift/time and defects rate? - How about a pareto chart? - Do
Electronics Forum | Fri Apr 25 08:48:25 EDT 2003 | davef
If what you say is accurate, two thing come to mind: * Pads on the board are incorrect for the tombstoning components. * Profile is different on the individual pads of tombstoning components. We have heard of, but never seen, components [tants] that
Electronics Forum | Thu May 01 17:49:33 EDT 2003 | jym2000
Did you check board orientation into the reflow oven? (The Layout components are the same products A & B?) Regards Jesus
Electronics Forum | Thu Apr 24 23:04:45 EDT 2003 | yukim
I've been struggling with this problem for a while. We have two products: A, which is Ok and B, with tombstone defect (0603 & 0805 capacitor chips). A & B have the same design: pad sizes, separation between pads, components orientation. Both have s
Electronics Forum | Wed May 07 09:02:17 EDT 2003 | Kris
Hi SnAg is a binary alloy and does not have the same effect as a ternary SnAgCu alloy as far the pasty range is concerned. But then paste only can do so much. The best way to do it is to have proper pad design, controlled placement and reflow. I w
Electronics Forum | Tue Jun 03 21:50:57 EDT 2003 | yukim
A question regarding the rampup slop: as we cannot make the preheat time long enough due to our reflow oven limits, a Loctite technician suggested we increase the rampup slope, between the initial point (25C) and 80C, to 4C/sec, as between these temp
Electronics Forum | Fri Sep 20 17:43:03 EDT 2019 | deanm
Looks like poor wetting/solderability to me. I don’t see heel fillets on the leads where the solder balls up. The solder has to go somewhere. It won’t flow where it won’t wet. Try printing a bare board and run through reflow. If the solder balls up o
Electronics Forum | Tue Jun 29 11:46:36 EDT 2010 | davef
Prins: Everyone has equations. Here's one some people use: False call rate = [Number of defective boards, but good at inspection]/[Total number of boards produced] Why don't you ask the people [that calculated the numbers that confuse you] how the
Electronics Forum | Fri Feb 13 03:26:07 EST 1998 | Brian S. Bentzen
Hi , The 4th stage in reflow soldering, the cool-down, I find is often over looked. A rapid cooling rate should give finer lead and tin structure with more bindings and thereby result in stronger solder joints. Can anybody give me some information
Electronics Forum | Wed Apr 10 05:29:08 EDT 2019 | SMTA-Tiberius
Hi there , We just got a 2000 litre Nitrogen tank for our Heller1809MKIII Reflow Oven , it has been installed and calibrated last week but now the Oxigen PPM doesn't drop below 3000 . Did anybody dealt with this issue before ?
