Electronics Forum | Sat Jul 02 06:19:01 EDT 2005 | Dhanish
My customer feedback they found one board with cold solder on the BGA ball.I looked at the picture,the ball looks very shining but I dont think that is a cold solder.What is the method can be used to confirm the colde solder beside cross sectioning t
Electronics Forum | Thu Jul 07 08:29:51 EDT 2005 | chunks
Check to make sure your conveyors are parallel. Also verify the the width to make sure the belts are supporting the board properly. Sounds funny, but I see this more times than anything else.
Electronics Forum | Thu Jul 07 06:48:15 EDT 2005 | davef
Alternatives are: * DSCC Columbus continues to maintain the QPL for MIL-I-46058C. [Engineering is unlikely to change.] * Use International Electrotechnical Commission Standard, IEC 61086 - Coatings for loaded printed wire boards (conformal coatings)
Electronics Forum | Thu Jul 07 18:03:27 EDT 2005 | russ
Sarag, FYI tombstoning is a functional failure. Tombstoning is where one end of the component is not soldered and is in the air above the board/solderjoint surface. You may be thinking of billboarding (part on its side with both ends soldered down)
Electronics Forum | Wed Jul 13 12:27:40 EDT 2005 | Bob R.
Are you seeing solder balling on your discretes when you print 1:1? Are you washing your boards?
Electronics Forum | Wed Jul 13 08:46:15 EDT 2005 | james
Does anyone else have problems with the frameless stencils on the MPM UP2500. I noticed after I do a stencil height adjustment it looks like the vacuum actually pulls the stencil to the board.
Electronics Forum | Thu Jul 14 01:43:09 EDT 2005 | pyramus
Solder paste used was Kester FL250M (no-clean).... components affected were only chip components 0603, no BGA & no IC components.
Electronics Forum | Thu Jul 14 13:45:32 EDT 2005 | slthomas
We've only seen it done by accident, and the result was a lot of white flux residue. You do need to make sure you get it all off, and to do so most likely means using a saponifier like sara suggested.
Electronics Forum | Mon Jul 18 00:00:35 EDT 2005 | adlsmt
I have nothing to add technically but we have been washing no-clean for years. Use very clean filtered DI water to avoid the white residue issue and some good detergent or sopanifier and you will get great results.
Electronics Forum | Fri Jul 15 16:27:55 EDT 2005 | davef
It depends on how much paste you put on the pads. Assuming your stencil is 1:1 to the pad and the solderability protection on the board is something other than HASL, we'd guess that your solder height is approximately 50% of your stencil thickness,
