Electronics Forum | Mon Dec 24 01:43:34 EST 2001 | sanmatech
Recently started running flex board with tin lead connectors. The problem being that when we receive the parts incoming connectors are all bright and shiny. Now after going thru the heller we encountered cold solder. At this time peak temp was at 186
Electronics Forum | Tue Jul 30 17:47:50 EDT 2002 | davef
Dewetting: Solder does not adhere to lead or land, caused by: * Poor solderability of lands. * Poor solderability of leads. * Solder paste integrity. * Lead plating integrity. Need more information, please: * What is dewetting [ie, component, pad, e
Electronics Forum | Wed Mar 16 20:11:03 EST 2005 | darby
KT, What sort of delta T are you getting? This does sound a bit odd. TCs are in EXACTLY the same position on each board? Something I only recently found out - according to Mark Cannon from ERSA re profiling, that you may wish to consider. 1.TCs sho
Electronics Forum | Sat Nov 05 07:17:25 EST 2005 | JeffP
That was the case with your oven but it is not so with ours. First, the distance from walls of the inner chamber to the product differs from one oven to another. Second, the dissipation of heat from metal heats up the air in the oven which in turn h
Electronics Forum | Wed Aug 16 13:52:24 EDT 2006 | russ
Oven settings are meaningless here. What does the board see? It is the paste we are concerned about not what the heaters are running at hehe. These solder balls are at the end of pad, which end? under the part or away from the part. I believe you
Electronics Forum | Wed Jul 11 14:45:22 EDT 2007 | samir
ECD, KIC, or any mfgr. of thermal profiling devices will charge a premium for "simple stuff". For example, ECD charges a grand for their "flux-o-meter", which is just a PCB with a hole pattern, a pallet, and pH-sensitive paper. You can easily ma
Electronics Forum | Tue Sep 18 07:52:29 EDT 2007 | davef
Does the change from supplier to supplier as a result of: * Board definition? * Differences in processing at fabs? 3 Specification Fir Tree General Technical Specification 3a Design/Layout: * IPC-2221 * IPC-2222 3b PCB Fab: * IPC-6011 * IPC-6012 * I
Electronics Forum | Thu May 01 12:46:19 EDT 2008 | dphilbrick
Thanks for the link Samir. Although this thread does have some good info in it I don't think it is hitting the exact point I am trying to resolve. This seems to talk to a one profile fits all for running lead and lead free paste. I want to know about
Electronics Forum | Tue Nov 05 09:57:45 EST 2013 | cuperpeter
Hello All, We have a problem with dewetting of solder paste. Problem is most visible on the pads without components (see attached pictures) and occurs randomly, 20% of PCB's. Pcb supplier sent us a cross-section of pads with thickness of Cu, Ni and
Electronics Forum | Thu Aug 17 05:56:39 EDT 2000 | Jacqueline
Hi Folks, Hope yous can help. I'm having a problem when reworking (placing) 40mil BGAs. One side seems to be collapsing more so that the other, resulting in the outer row of balls not properly reflowing and making the connection. This is only happeni
