Electronics Forum | Sat Sep 15 13:00:44 EDT 2007 | slthomas
220 should be plenty although if they're lead free you might need a little more heat. Is it possible that you've got a paste volume issue (stencil design, clogged apertures), or maybe the footprint isn't right for the part? I had this same problem
Electronics Forum | Mon Sep 10 15:49:28 EDT 2007 | mun4o
Hi, the solder on the pad is not molt.Temperature of the leads is about 220*C( I change this T from 214 to 232) but result is same - solder is granular and not diffuse.I think the T on leads is not enough high,bu I can't increase because the max T on
Electronics Forum | Tue Sep 11 08:00:46 EDT 2007 | hussman
HOW did you change the temp? Stay that course till you achieve the temp you need. Try slowing the conveyor as well.
Electronics Forum | Thu Sep 13 13:36:46 EDT 2007 | russ
switch pastes and see what happens, Kester had issues with their fluxes a little while ago and you may have gotten one of the bad batches. R
Electronics Forum | Mon Sep 17 01:43:05 EDT 2007 | mun4o
hi, finishing is lead free HAL, Tpeak=214-232*C in diferent profile, wich we made.
Electronics Forum | Thu Sep 13 21:56:09 EDT 2007 | wayne_
should have ask the technical support personnel from Kester to come over to your factory and solve the problem on-site. Let them see what is wrong with their product, then they will improve it further....or straight away tell you they do not have sol
Electronics Forum | Fri Sep 14 09:34:17 EDT 2007 | russ
you using a ramp soak spike or ramp to spike profile? you may be burning out your flux in preheat if you ramp to fast or for too long, most pastes have 2 activation points for their flux one at low temp and one at higher temp. Try a ramp to peak pr
Electronics Forum | Thu Jan 08 15:03:40 EST 2004 | dwzeek
We have an ongoing problem with our QFP144 packages soldering. It has not received much attention until late due to some customer failures. Most of the failures would show up in ESS testing and be repaired. The failure rate is about 2 in 1000 parts f
Electronics Forum | Thu Jan 08 16:16:09 EST 2004 | Dean
My first concern would be the choice of solder paste you have. There are better chemistries out there that far exceed the capabilities of the 609 2. Yes, the part will partially float on the solder (assuming plastic qfp). Cross sectioning would sho
Electronics Forum | Thu Aug 05 09:09:01 EDT 2004 | Kris
is QFP lead co plnarity an issue ? If the QFPS are not sitting in the paste and that can be random if they are very close to the manufacturing tolerence Thx
