I have a 3 year old assembly that has most of the SMT joints coming off the
pads. The PCB was HASL finished and the SMT components were pasted and
convection re-flow The joints appear to be good visually, but if probed
lightly the components will pop off, leaving only a dull copper pad
exposed. Appears the copper was contaminated prior to HASL, but we should
have noticed an obvious exposed copper prior to assembly. Also the assy.
has thur hole that get wave solder on bottom side after SMT. Could the 2nd
process re-flow the smt without flux and start oxide on copper. I am open
to any input.

---------------------------------------------------------------------------------
Technet Mail List provided as a free service by IPC using LISTSERV 1.8d
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt delivery of Technet send the following message: SET Technet NOMAIL
Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315
---------------------------------------------------------------------------------