Electronics Forum | Tue Jun 02 17:32:53 EDT 2015 | jldowsey
Les, Some of the answers to design or stencil aperture/placement machine depend upon what is the current spacing between your components which you didn't specify. Chip components such as 0402's and 0201's typically have very small reductions in pas
Electronics Forum | Wed Nov 07 18:37:27 EST 2001 | steven
sometime hand solder can cause also. no necessary have to be paste n reflow.:) now i'm facing bridging on 0402 components pads. any suggestions on spacing distance as we're going to re-design the pcb.
Electronics Forum | Mon Dec 06 09:28:11 EST 1999 | Dave F
Glen: So that's this metal? Is it in the area of PTH or SMT solder connections? Etc, Etc. Assuming its near connections where pasted is reflowed ... Reflow defects, bridging: misplaced components, high placement force mushrooms paste, too much p
Electronics Forum | Sat Jun 25 09:26:43 EDT 2005 | mskler
What is stencil thickness & what is the pitch of your component.What is your cleaning processor for stencil.
Electronics Forum | Tue Dec 14 12:41:56 EST 1999 | Kris W
Glen, Although the previous answers probably fit the problem you are having, we recently found that during pin insertion on an Autosplice machine, the gold was flaking from the pins and lodging between the legs of surface mount components. It would
Electronics Forum | Sun Sep 09 10:53:05 EDT 2001 | bentzen
For reflow soldering, you are correct ! The higher surface tension of the solder paste in nitrogen atmosphere can increase the number of solder bridges if the component or solder paste print is inaccurate. Another defect that might increase is tomb
Electronics Forum | Mon Aug 23 14:09:56 EDT 2010 | davef
Similar to Coop's comments, above ... Bridging: * Mis-placement: misplaced components, high placement force mushrooms paste * Too much paste: HASL thickness, lead finish, poor underside support, poor underside wipe frequency, printing with too lar
Electronics Forum | Mon Aug 23 03:12:57 EDT 2010 | grahamcooper22
Possible route causes of bridging on fine pitch ICs are; too much paste (stencil aperture wrong), poor print quality (paste smudges during printing), pcb pads not flat depending on the solderable coating, paste has poor cold slump properties, too muc
Electronics Forum | Mon Jan 15 15:40:18 EST 2007 | pyro747
Having problem with a 2X50 SCKT Strip PTH component(fine pitch) bridging on the wave. The PCB runs in wave pallets. Just wanting to know what successful findings have been done to eliminate bridging? Pallet angles? Copper or titanium inserts? Air kni
Electronics Forum | Fri Dec 27 12:12:29 EST 2019 | slthomas
As has already been mentioned, black residue is usually either from dross or just a dirty pot, pump, baffles, etc.. I also saw that maaaany years ago in a system that used a flawed oil intermix "feature" but hopefully those systems are long gone.
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