Electronics Forum | Mon Mar 20 10:54:36 EST 2000 | Glenn Robertson
Jack - The last time I checked IBM was specifying a minimum of 4800 cubic mils of paste for each pad. This is required for acceptable reliability, not just to make the connection. There is no way you are getting that volume with a 5 mil stencil
Electronics Forum | Sat Mar 18 07:33:34 EST 2000 | Dave F
Jack: Two concerns with column devices: 1 Coplaniarity of the device and the board. 2 Adequate solder that you mentioned, becuase the columns will not be reflowing and you need to cloatthem with solder. You didn't describe your aperture, but even
Electronics Forum | Wed Jul 24 17:25:01 EDT 2019 | davef
Your solder stencil design should follow all basic rules for solder stencil design are followed in accordance with IPC-7525 including adherence to an area ratio of 2:3 or greater and an aspect ratio of 1.5 or greater.
Electronics Forum | Mon Oct 15 10:51:49 EDT 2001 | davef
On over printing, the general issues are: * Paste deposits being so large that when reflowing, collapse onto many, rather than a single solder mass. * Paste expanding during heating and being close to other solder deposits and bridging [as you say].
Electronics Forum | Sun Jun 07 09:58:12 EDT 1998 | Bob Willis
Dummy pads can work well on through hole parts and are often used in the Far East and on IBM products. If you take a VCR or TV board you will often see this trick being used. Alternativly you can stagger the pads at the trailing edge that works well.
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