Electronics Forum | Thu Feb 16 13:08:13 EST 2012 | gaz
Is that the "general metal loading" spec? We are using AIM ws400 sac305, so 88.5%.
Electronics Forum | Fri Sep 17 13:51:43 EDT 2004 | huib
We know from experiments that the structure of Sn can be manipulatedby means revese pulse-plating. This means alayer with less pits and thus a lower mminimum thickness is needed. www.ppcs.nu
Electronics Forum | Mon Jun 13 14:34:16 EDT 2005 | peter ng
The stencil thickness should be 5.5 mils.The squeeze speed around 20mm/s,print gap 0.15mm,print separation 0.3mm/s.
Electronics Forum | Thu Mar 02 13:19:10 EST 2006 | Wave Master Larry
WELL, I heer that thikness was always wrong where I work, and for what ever reason the engineering department chose 6 milimeters. Personaly i would of gone 8 myself. I look under the magfying glass and always noticed in-suficient solder on the gull
Electronics Forum | Thu Mar 02 13:29:30 EST 2006 | russ
6 mils maybe? instead of 6mm? We go down to 5 mils and up to 7 with 0603. You could even use a 4mil stencil for these without any problems. The .2mm (.0078")apart however might get you in trouble unless your equipment is rock solid.
Electronics Forum | Mon Mar 13 04:18:42 EST 2006 | pedestrian
0.2mm gap between parts is small and easy to solder short. I prefer 5mils or 4mils.
Electronics Forum | Tue Aug 17 13:24:47 EDT 2004 | blnorman
We have parts that have electroplated tin over nickel. The mfg. assures us the minimum thickness of the tin is 5 microns. Cross sections have shown many instances of 1 micron and pits that go down to the nickel barrier layer. A request for thicker
Electronics Forum | Thu Mar 02 13:04:22 EST 2006 | Chunks
0603 parts at .2mm spacing is pretty easy. But are there any other parts, like fine pitch QFPs? Is your board HASL or something else? Is there resist/mask between all pads? If it's just 0603's at .2mm, then you can probably go 7 mils and get good
Electronics Forum | Mon Jan 23 22:53:31 EST 2012 | davef
= 0.66 aperture opening to the stencil wall has been shown to provide the best transfer efficiency and repeatability of the deposited paste. Values from 0.66 to 0.8 insure a good paste release from the stencil. The biggest impact on area ratio is the
Electronics Forum | Thu Jun 09 13:30:34 EDT 2005 | PWH
I would suggest 7mm thick "Durostone" as a carrier material. Cut lip/pocket for PCB so it is 0.05" thinner than thickness of PCB. Allow 0.010" gap on all sides of PCB. Machine lip to width between 0.050" and 0.100" to support under perimeter sides
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