TECHNET Archives

September 2007

TechNet@IPC.ORG
Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
Re: Pin / Pit Hole at solder joint of SMD passive
From:
Bob Willis <[log in to unmask]>
Reply To:
TechNet E-Mail Forum <[log in to unmask]>, Bob Willis <[log in to unmask]>
Date:
Wed, 5 Sep 2007 14:30:22 +0100
Content-Type:
text/plain
Parts/Attachments:
text/plain (79 lines) 
Outgassing can come from the surface of the plating of components, see this
example video clip and watch the outgassing on the surface of the plating
away from the solder paste as it reflows.

www.ASKbobwillis.com/video%20clips/bobwillis814.wmv 

When you see the hand with the pointed stick don't worry this video was part
of another experiment.

You should not always blame the paste, profile or board finish when you see
voids or gassing.

Many thanks

Bob Willis
2 Fourth Ave, Chelmsford, Essex, CM1 4HA England
Tel: (44) 1245 351502
Fax: (44) 1245 496123
Mobile: 07860 775858
 
www.ASKbobwillis.com
 
Book your place on Bob's "Step by Step Failure Analysis Workshop"
www.ASKbobwillis.com/faworkshops.pdf
 
Book a place on our "Land Grid Array Design, Assembly, Inspection & Rework
Workshop" www.ASKbobwillis.com/lgaworkshops.pdf 

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Lum Wee Mei
Sent: 05 September 2007 13:40
To: [log in to unmask]
Subject: [TN] Pin / Pit Hole at solder joint of SMD passive

Hello,
 
While soldering SMD passives (0805, 1206 packages) onto Tin/Lead finished
board, the operator noticed the solder bubbles as it melt. On further
heating, the good solder fillet is formed between the termination and the
solder pad. However, a tiny "dimple" is left in the centre of the solder
joint. While not all has tiny "dimple" left behind, bubbles do occur during
most of the operation.
 
What could be the cause as there is no change to the material used (solder,
flux, soldering iron, etc)? 
 
Sometimes back, someone asked about blowholes and the cause is that it is
due organics in electroplating. As my board is Tin/lead finish, is the cause
the same? 
 
Thanks and regards,
Wee Mei
 
 

---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
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/contentpage.asp?Pageid=4.3.16
for additional information, or contact Keach Sasamori at [log in to unmask] or
847-615-7100 ext.2815
-----------------------------------------------------

---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
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/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------

ATOM RSS1 RSS2