Electronics Forum | Thu Mar 27 11:39:27 EST 2003 | kenlchin
Hi,mantis, I has experienced this case.when we run a model ,misalignment and tombstone of some 0805 resistors and 1206 caps always occured.we have taken many actions,such as adjusting reflow parameter&printing parameter,checking pcb and parts soldera
Electronics Forum | Fri Jan 28 04:03:51 EST 2011 | grahamcooper22
Print then dispense in the areas you need extra paste. Why can you not use a stencil which has areas etched away around component patterns to thin the stencil down....for example a 150 micron thick stencil etched to 120 or 100 microns in specific are
Electronics Forum | Wed Mar 23 05:17:23 EDT 2011 | arwankhoiruddin
Hi All. I want to know what is the IPC/JEDEC standard for solder paste printing defects. From the brochures of SPI Machines, the recognized defects are excessive, insufficient, misalignment, no solder, bridging, and solder shape error. What document
Electronics Forum | Fri Aug 22 00:25:20 EDT 2003 | mantis
Kenny, Out of curisoty why do you need to paste the vias.Is it due to contact reliability at test.Can these vias not be soldered during wave process (if any).Can the Style of probe used in the ICT test fixture not be changed to accomodate these unsol
Electronics Forum | Thu Mar 20 18:39:30 EDT 2008 | cmckissick
I am not a big believer in these systems, unless you are doing a no-clean, multi-shift operation with minimum changeover. If you are a small batch shop, the amount of solder paste you end up wasting can actually be the same or more, if you are not r
Electronics Forum | Fri Dec 17 08:05:00 EST 2004 | davef
Your solder paste is talking to you, follow its message. Listen to the paste. Be at one with the paste. If you insist on ignoring the message of the paste, add more paste, if you just need to complete the last board or so, but you really should ju
Electronics Forum | Tue Jun 28 13:04:08 EDT 2005 | slthomas
Are you saying that increasing the frequency of cleaning to every 3 boards *reduced* bridging, or that it's just something you tried? I don't understand why that would help(in my experience it has reduced "insufficient solder" conditions but not brid
Electronics Forum | Fri Mar 04 15:22:17 EST 2005 | russ
Glad to hear a little success from ya Duckmann! i have stenciled mask in the past and I can tell you that stencils are expensive. They are basically a step stencil, you will need full thickness for the area(s) you are going to apply mask and you wi
Electronics Forum | Tue Jan 30 04:20:26 EST 2007 | Phil J
Print your paste onto a ceramic tile, place the offending component onto it and send through the reflow oven; then observe the results. You will soon see if the component is solderable!
Electronics Forum | Thu May 26 08:52:42 EDT 2011 | davef
Phil Zarrow wrote a useful paper that could help in evaluating paste. Here read it ... Evaluating Solder Paste � Not An Option Contributed by Phil Zarrow of ITM an Independent SMT consulting firm With soldering being the dominant source of assembly
