Electronics Forum | Thu May 18 09:18:33 EDT 2006 | Chunks
Hi dwelch123, 8 mils seems a bit thick to me. I would normally go 6 or 5 mil for fine pitch such as this. One other area to check is the the snap off. Are you using the slow snap off or just lowering the board right after print? If so you should
Electronics Forum | Wed May 17 13:48:37 EDT 2006 | dwelch123
I'm having trouble printing leads on a fine pitch part. The lead is only .008". I'm using a DEK 265 with metal squeegee and using WS200 multicore solder paste.The stencil is laser cut and polished. I've experimented with different pressures and diffe
Electronics Forum | Thu Jun 16 00:24:29 EDT 2005 | mskler
Hi everybody, Can some body tell me that what stencil thicknes is required for the 16mil QFP. I am getting bridging as well as dry at QFP pins. What type of solder 1. Viscocity 2. mesh size 3. flux contents Should be used for this type
Electronics Forum | Tue Sep 17 15:03:33 EDT 2002 | ccross
I am working with fine pitch components (15-20 mil) and having soldering problems and would appreciate some opinions. 1) How much of an effect does pad size have on bridging? 2) How much of an effect does solder paste grain size have? What is the re
Electronics Forum | Wed Sep 18 06:53:05 EDT 2002 | CH
1) For solder short, pls check the paste height. Too much vol will cause short. For 15 mils use 5 mils thickness stencil if possible. Check profile preheat time to prevent hot slumpof the paste. 2) type 4 powder will be better for 15 mils pit
Electronics Forum | Tue Sep 30 14:06:04 EDT 2008 | realchunks
What pitch? You can go 5 mil or even 6 mil stencils depending on your screen printer. Also what do you consider "less solder"? What defect are you having. Remember on a QFP you use the heel filet to determine proper solder joint - not the toe.
Electronics Forum | Thu Oct 02 08:26:41 EDT 2008 | rway
We had similar issues until we went to a 6 mil stencil thickness.
Electronics Forum | Tue Jan 08 09:23:18 EST 2013 | lock_2002
This is a question regarding soldermask between pins of fine pitch devices. The majority of our production designs end up with at least 2-3 mils of copper thickness on the external layers due to blind vias, wrap plating requirements, etc. Our curre
Electronics Forum | Wed Sep 18 12:31:16 EDT 2002 | dragonslayr
My suggestion is to conduct a Design For Manufacturing (DFM)study on the assembly in question. Pay particular attention to the pad sizes, component lead dimensions and satisfy yourself that those two factors are correct. Given that pads match compone
Electronics Forum | Tue Jan 15 10:53:18 EST 2013 | boriskilk
We wouldn't advocate extending the soldermask beyond the component body but yes to ganging for fine pitch. To ensure we don't run into issues with flaking our preference is not to add solder mask when the space between pins is less than 6 mil.
