If the pad ends in a square shape, the solder, as it melts,  is
foreced to take the same shape, which is not what nature wants it to. So,
the solder that is at the corners wants to spill off and it does when the
boards vibrates as it moves across the oven. This is one of the causes of
solder balls in my opinion
        Pads and leads shoud be rounded to be close to the natural shape of
melted solder. Some food for thought.
        Regards,
        Ramon



> Have you tried oblong apertures? As far as I know, studies made showed
> overprint of something like 125 mils didn't cause solder balls.
>
>
>
>

---------------------------------------------------
Technet Mail List provided as a free service by IPC using LISTSERV 1.8e
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 or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/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
-----------------------------------------------------