Electronics Forum | Fri Feb 09 16:38:17 EST 2001 | larryk
PK11, Metro- http://www.metro.com Fancort- http://www.fancort.com Larry
Electronics Forum | Tue Jun 04 16:14:25 EDT 2002 | Bob
Did I say leaching I meant bleeding. Doh!!
Electronics Forum | Thu Jun 06 07:33:04 EDT 2002 | cyber_wolf
Whoa ! sorry guys I thought my post from yesterday did not go through. Anyhow they both mean the same thing.
Electronics Forum | Wed Aug 19 16:21:15 EDT 1998 | Doug Nebel
Steve, Ok Indust. made a solder fountiain ( SA-5201) that we use for the situation you describe. I was told that OK no longer make it, but you might check and see if this is true. It listed at about $3,500. I also saw that BONKOTE make a similiar
Electronics Forum | Tue Jun 04 15:58:06 EDT 2002 | Hussman69
Hmmm... I know the Vitronics oven had bigger motors on em', but I don't think they're blowing molten solder balls around. You did say you changed your profile and stencil designs, which helped, but didn't exactly state what ya did. I believe this
Electronics Forum | Tue Jun 04 16:12:41 EDT 2002 | Bob
The original profile had a higher ramp rate, and the apertures were 100%. The ramp rate is now much gentler and the addition of a small soak area around 160 � 170 degrees should burn off any excess flux. Appertures are now smaller and we get no leac
Electronics Forum | Tue Jun 04 17:05:52 EDT 2002 | davef
Solder balls floating around on the air currents of a reflow oven. I sincerely doubt it. Could the solder on your gold fingers be from: * Excess placement force during P&P? * Ejactula from solder deposits during rapid preheat ramp rates? * Ejactula
Electronics Forum | Wed Jun 05 12:22:45 EDT 2002 | Bob
No. Placement force is fine. Also boards have been inspected prior to reflow using microscope with no evidance of misplaced solder balls. The ramp rate has been reduced to acceptable limits, typically .8 - 1.5 degrees per sec. Outgassing from eithe
Electronics Forum | Thu Jun 06 12:24:30 EDT 2002 | cyber_wolf
Brad your theory sounds good, but I have seen this happen at very low ramp rates .5 deg to 1.5 deg C rate of rise a sec. with the same soak duration you mentioned. If flux spattering is the case and you are using Alpha paste..switch to Indium and yo
Electronics Forum | Thu Jun 06 16:26:36 EDT 2002 | Bob
Thanks for all the input. It is pretty much what we have checked for, microscopic analisys before printing, assembly and reflow, but like we all seem to agree one ball of solder is hard to find. The boards are full QWERTY keypads with a few LED's a
