Electronics Forum | Wed May 03 12:12:46 EDT 2006 | Chunks
All good points by Pee Wee Herman; your solder balling may appear if you don't currently have stencil with reduced apertures or "homeplate" design. "Flux is solders' muscle."
Electronics Forum | Tue May 16 17:58:46 EDT 2006 | russ
Yeah chunks, I do not know if it is spec or guideline, I refer to the "courtyard" grids for design, don't have the book handy so i am not sure if you are in the right place or not. i'll check though soon and post russ
Electronics Forum | Tue May 16 18:01:50 EDT 2006 | russ
Steve just mentioned the 782 for ammo to customer, we usually get "it doesn't meet IPC" so we then say it was not designed to. let the pissin contest begin! Russ
Electronics Forum | Thu May 18 15:42:17 EDT 2006 | slthomas
In this case we're not the customer of the fabs, OUR customer is. So, our customer provided us with damaged material. However, we can't prove that the damage is the cause of the failure because no one has the expertise to troubleshoot the board adequ
Electronics Forum | Fri Jun 02 08:50:47 EDT 2006 | russ
Hmmm interesting, we utilize 5 mil stencils and print to same height as you and do not experience these failures. May I ask what paste you are using and what the spacings are of your pad design? But anyhow, if it works it works.
Electronics Forum | Fri Jun 09 08:17:07 EDT 2006 | amol_kane
did you look at the pad vs the stencil design? are you putting down enough solder paste on the pads? what are your reduction ratios for these packages?
Electronics Forum | Wed Jun 14 08:33:30 EDT 2006 | davef
You're not that late. Every time we've been involved in part marking removal, it was done to make it difficult to pirate a board design.
Electronics Forum | Wed Jul 12 13:56:49 EDT 2006 | muse95
From a design/test/troubleshooting perspective, I would pick a QFP hands down - I can't probe a hidden solder ball.
Electronics Forum | Thu Jul 06 04:41:58 EDT 2006 | Rob
MF300S is quite an old flux, & a lot has happened since then on the flow solder front - are you sure it's designed for Lead free, or is it just a traditional flux that SHOULD work OK with Lead free?
Electronics Forum | Tue Jul 04 07:40:22 EDT 2006 | slaine
I had a couple of reps in from Indium a few weeks back, and they were promoting a flux for rework that was designed to have low SIR, No clean. Havent tried it yet. The product is Flux NC 771, might solve your problem? Regards Slaine
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