Electronics Forum | Mon Dec 27 12:24:47 EST 1999 | RICK_EEI
Hi everyone. We use a small ultrasonic aqueous cleaner. After each PCB we hand solder, (water soluble) we place it in the cleaner immediately. Lately we have had some problems with the solder joints appearing to be corroding away. We tried lowering t
Electronics Forum | Tue Dec 28 15:35:21 EST 1999 | Mike Naddra
Edmund, An 0603 component should not fall from the board durring an inverted reflow pass, provided that: Your land geometries are correct for the package type (Start with SM 782 guidlines)- as surface tension of the liquidous solder is what holds
Electronics Forum | Tue Dec 14 10:36:42 EST 1999 | Paul Peterson
I recently encountered reflow soldering defects on a pair diode package, the smd pad had a green contamination, I'm convinced that this is not oxidation. The no-solder condition appears to be caused by a sloppy soldermask process, although over the y
Electronics Forum | Fri Dec 03 19:44:34 EST 1999 | Russ
Hello all, I am in the process of converting our facility to noclean processes. So far I am experiencing troubles with soldering to gold finishes. The finish is an H.P. type1. The solder joints appear dull and grainy. They seem to be very strong
Electronics Forum | Thu Dec 02 23:43:23 EST 1999 | Kantesh Doss
We have a serious misalignment problem of D-Pak components (Specifically Motorola's part number MJD-3055/MJD-2955)following reflow soldering process. We are using Alpha Metals UP78 solder paste. Our reflow oven is Nitrogen inerted and our oxygen leve
Electronics Forum | Fri Dec 03 18:01:39 EST 1999 | Dave F
Chris, Two points of perspective are: 1 Solderability: The shelf life of components has elapsed when they are no longer solderable. There's tons of variables that affect this, but keys are: * Intermetalics grow as a function of temperature. * Th
Electronics Forum | Thu Nov 18 08:43:30 EST 1999 | Will Buehler
We currently stuff parts on one side and use a reflow oven. We have been told that many companies are stuffing both sides without high-temp solder or glue. I understand that glue is usually only needed for wave soldering processes. Is it true that
Electronics Forum | Thu Nov 11 14:55:23 EST 1999 | Dave F
Dave: I think you�re correct. The solder balls are probably from either: � Excessive paste � OR � Paste "exploding/popping" during reflow � OR � Some other variable. Two things: 1 It�s virtually impossible to determine the cause of your ball gen
Electronics Forum | Mon Nov 15 12:09:55 EST 1999 | Dave F
Steve: Continuing with Dan�s thinking, generally, "poor release" (paste hanging-up in the stencil holes) could have three main (or combination of) causes: 1 Equipment: Stencil is too thick. Specifically, your 0.006 should be OK, providing you don�
Electronics Forum | Fri Oct 22 11:37:38 EDT 1999 | Brett Gordon
Working DFM SMT issues with respect to a client's artwork together with a heavily modified solder stencil, I was able to reduce 0402 tombstoning from 80% across the board to 3%. I winged the aperture reductions, but are there any "rules" or guidelin
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