Electronics Forum | Mon Dec 18 13:00:34 EST 2006 | realchunks
Hi John, Depending on your board, it could make a difference. Copper finishes might leave that part of the pad exposed, which is a no-no in most places. Where as a HASL board prolly won't care if you pulled the print back. On the other end, over
Electronics Forum | Wed Jul 17 12:07:48 EDT 2002 | dragonslayr
DaveF is correct in directing you to the archives. This problem type has been discussed many times, it is quite common. Questions to ask yourself and provide us with answers are: It always happens or random? All assemblies or just one? solder paste
Electronics Forum | Sat Apr 19 12:00:07 EDT 2003 | modeltech
I am completely new to SMT design and for my next project I plan to use SMT for the first time. Since production volumes of the PCB's will be low, hand soldering is definitely an option, and will be necessary for my prototype PCB assembly. My proble
Electronics Forum | Wed Dec 09 10:45:56 EST 2015 | huske
I've put down a SOT223, close enough to your 3pin transistor, in the same situation you have. The large pin was to be soldered on a large exposed ground plane in the corner of a board, over 2"x2" exposed area. We left the paste file as is, so where
Electronics Forum | Mon Aug 25 10:36:05 EDT 2008 | davef
Yes, it's peculiar that the layout of this board is so disorganized * Pads are not round, uniform, or the same size * Exposed traces have different thickness
Electronics Forum | Thu Feb 02 10:10:20 EST 2023 | tommy_magyar
Perhaps google this, as you will find very interesting articles. For scientific explanation look up solder fatigue on Wikipedia with references added. A more in depth explanation you can find on the Digikey forum where you will find other people like
Electronics Forum | Wed Aug 07 17:20:17 EDT 2019 | orbitcoms
The aperture over the pads is set to 95% coverage of the pad. The stencil is 0.12 mm thick.
Electronics Forum | Wed Aug 07 12:41:58 EDT 2019 | slthomas
Are the apertures on the stencil reduced in width or 1:1 with the pads? It depends on the pad width and foil thickness but we usually reduce aperture width for any part that results in an aperture wall spacing of less than 8.5 mils.
Electronics Forum | Thu Oct 01 06:22:48 EDT 2009 | rajeshwara
We approved the Reflow Profile from Cookson Solder Paste Manufacturer we are using. Now I am suspecting on method of vias designing below that QFP.There is exposed pad for that QFP and we print solder paste there , but when i see under x-ray there is
Electronics Forum | Wed Aug 07 18:00:56 EDT 2019 | orbitcoms
I am doing another run today. I'll check how central the machine is placing the components onto the pads. I wonder if the part is off slightly and smudges past across the pins? What about if the part is being placed too deep into the paste?
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