Electronics Forum | Tue Dec 05 03:39:39 EST 2006 | pavel_murtishev
Good afternoon, Due to problems with power connector soldering I have to overprint paste on pads for this connector. Stencil thickness is 125um and I cannot make it thicker. Area ratio of chip resistor assemblies limits stencil thickness to 125um. R
Electronics Forum | Tue Dec 05 08:23:14 EST 2006 | davef
How about a stepped stencil? Not ideal but ... As far as overprinting goes, try: http://www4.uic.com/wcms/WCMS2.nsf/index/Resources_44.html
Electronics Forum | Wed Dec 06 06:09:02 EST 2006 | Loco
Would say about the same as above, 8mm according to a cookson presentation we had, of course it would depend a bit on the paste you are using.
Electronics Forum | Wed Dec 06 07:24:22 EST 2006 | davef
Successful solder paste overprint is a function of the solder paste rheology, solder mask and through hole component stand off. * Solder mask with a high surface energy will permit a larger overprint than a solder mask with a lower surface energy. In
Electronics Forum | Wed Dec 06 16:17:31 EST 2006 | Mario Scalzo, CSMTPE
Normally, we try to limit the over print of the paste to the width of the pad on both sides. If you are using 500um pad, then I wouldn't try over a 1500um aperture. Mario Scalzo, CSMTPE, Dartmouth 6 Sigma Green Belt Technical Support Engineer - Ind
Electronics Forum | Wed Dec 06 08:29:50 EST 2006 | David
Hi Pavel, We regularly use over printing on a multitude of problem parts including fine pitch QFP's. In an Automotive Environment the only thing you can change without a mountain of paperwork is the stencil. best way to work out how much you can get
Electronics Forum | Fri Oct 29 13:45:03 EDT 1999 | David Vulcano
We are placing several axial components that have STEEL leads. Have noticed that the steel components do not get good flow thru(we manufacture to IPC-A-610 Class II Standards which reqires 75% flow thru) We are using Seho Wave Machines with Nitroge
Electronics Forum | Tue Mar 06 09:42:15 EST 2007 | realchunks
Hi Mark, Solder paste will not flow on Ni like it appears on HASL. Where you print it is where it will reflow. Has been like that for years. As a CM you should re-engineer / recut your stencil to provide proper solder joints. I seriously doubt i
Electronics Forum | Mon Mar 05 22:42:30 EST 2007 | davef
On your ENIG thickness requirements, search the fine SMTnet Archives for previous discussions, like: http://www.smtnet.com/forums/Index.cfm?CFApp=1&Message_ID=33661 On determining if your board will solder properly: ANSI/J-STD-003, Solderability Te
Electronics Forum | Wed Feb 02 13:05:51 EST 2005 | russ
Process flow 1.Remove part - It may be necessary to bake assembly prior to removing. 2.Remove remaining solder from part 3.Apply flux to part 4.Apply solder spheres to part 5.Reflow part You may want to bake component before re-installing 6.Apply
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