Electronics Forum | Fri Dec 20 15:38:53 EST 2013 | island2013
Aperature layout on your stencil could be a root cause as well. Home plate design aperatures have cleared this issue up for me in the past. If it's a clean product, running through the wash may get rid of quite a few of them. Also check your IPC s
Electronics Forum | Mon Sep 19 09:16:24 EDT 2016 | markhoch
Hi Shriram, Are you saying that there is a trace running between the pads for this 0603 capacitor? If so, this design may be causing a gasketing issue between the stencil and the PCB. The uneven height prevents the stencil from sitting flat on the PC
Electronics Forum | Fri Aug 07 10:14:43 EDT 1998 | RWW
| I'm currently running a double sided paste smt board loaded with 0603's, on the secondary side. Many of the 0603 devices tombstone during reflow if the parts are not perfectly centered on the pads. Is this caused by the .008 foil thickness? Has any
Electronics Forum | Thu Aug 16 13:46:06 EDT 2001 | Hussman
Hi Pavel, I'll bet you're talking after reflow - so in a nutshell - it is too much solder. Paste goes under the R or C and rests on the mask after placement. During reflow, this excess paste balls up along your part (wow, look Ma, no rocket scienc
Electronics Forum | Wed Nov 10 18:02:54 EST 1999 | John Thorup
Hi Dave Sounds like what we call a "squeeze ball". Usually caused by excess paste squeezed over the mask between the pads of the component when placed. This sometimes escapes the pull of surface tension back to the fillet and escapes to the side, us
Electronics Forum | Mon Aug 14 14:27:00 EDT 2017 | emeto
Here is some food for thought. Try to answer these questions yourself and I am sure you will see huge improvement. Reasons: - Bad PCB design - Plating-uneven HASL cause more than OSP Au/Ni or Silver - Poor paste and print quality - uneven paste ca
Electronics Forum | Sat Jan 06 10:52:09 EST 2001 | Steve Thomas
I don't know the specs. of our MSHII's, as I'm sort of detached from that part of the process, but supposedly they are capable. Panasonic also recommends we buy all new feeders (well, big surprise there), because of the risks involved with retrofitti
Electronics Forum | Tue Jun 04 20:34:28 EDT 2002 | russ
Jason, Excessive thermal ramp rates, misprints, improper pad design, paste type, placement pressure, all can cause solderballs. Do the pads on this board meet IPC 782 criterias? I have found that too much pad underneath component can cause this. A
Electronics Forum | Thu Feb 13 19:08:31 EST 2014 | darby
Have to agree with Sr Tech and Spoilt - you'd have to really mistreat your paste these days for it to be the root cause. However, try another paste to eliminate that; making sure you abide by the suppliers specs. Pad design, stencil design,(includin
Electronics Forum | Tue Oct 31 14:52:25 EST 2000 | Dr. Kantesh Doss
Hi Antonio: You clearly have printed excessive amount of solder paste on the pad. You can reduce the amount of paste by one or two methods: 1. Switchover to 5 mil thick stencils. 2. Change the design of your stencil openings (at the discrete compone
