Electronics Forum | Tue Jun 02 07:31:55 EDT 2009 | scottp
Early on when we started looking at BGAs we tried dipping. We've done it in production for a couple decades with flipchips. Dip fluxing BGAs worked fine in the lab but we ended up starting production with screen printed flux for cycle time reasons.
Electronics Forum | Fri May 08 16:30:59 EDT 1998 | Chrys
| I am running boards with gold fingers on a pallet for | masking purposes. The pallets worked fine for a while | but know the gold fingers are getting solder on them. We | have tried everythin: new pallets, cleaning the pallet | and board to be s
Electronics Forum | Tue May 19 08:48:05 EDT 1998 | Aric Parr
| | I am running boards with gold fingers on a pallet for | | masking purposes. The pallets worked fine for a while | | but know the gold fingers are getting solder on them. We | | have tried everythin: new pallets, cleaning the pallet | | and boa
Electronics Forum | Fri Sep 11 15:27:50 EDT 2015 | u4bga
Hi! We're noticing white spots on 2 PCBAs after the selective soldering & DI Wash processes. ----Facts---- 1) The marking is on all boards, irrespective of date code 2) It only happens on leads that have been selective soldered 3) The pattern of w
Electronics Forum | Thu Sep 05 18:15:15 EDT 2002 | pjc
There are chemistries out there that will solublize some post-solder NC flux residues. I have had success with Zestron material Vigon A200 and Petroferm material Hydrex DX. Go to http://www.zestron.com and http://www.petroferm.com These are chemical
Electronics Forum | Thu Jan 27 04:02:00 EST 2011 | richiereilly1
Hi, We had a similar issue to this. When we examined the boards at x-ray there were no apparent defects, We sent the boards for Dye and pry testing and we found that there were crack or gaps between the paste on the PCB and the BGA ball. basically th
Electronics Forum | Wed Mar 15 09:42:17 EST 2006 | slthomas
Is the lead leaving a depression in the solder that wetted the pad or is there maybe just not enough solder to fill the gap?
Electronics Forum | Tue May 09 14:19:52 EDT 2006 | Larry (not THAT Larry)
Smartasp - What are your lead to hole ratios like? Dial down the flux and open up the holes, if you can. Keeping at least a 14-20 mil gap between min hole/max lead solves the hole fill problem. L
Electronics Forum | Wed Mar 15 09:36:43 EST 2006 | vicknesh28
Thanks Marc. I will try the things that u have mentioned. I am guessing if the flux can find its way between the bottom foot of the lead and the paste, there has to be a gap between the solder paste and the lead when reflow takes place. As u have sai
Electronics Forum | Wed Oct 30 02:12:39 EDT 2019 | jags
yes and thanks for this feedback. we clean with degreaser ( strong) and flux is rosin with 10% in the paste (koki). we clean after second reflow . the gap time from bottom to topside completion is 10 hours. cleans with this time. my even after 20 h
