Electronics Forum | Fri Sep 21 14:03:45 EDT 2001 | jschake
I have observed solder balling for all aperture sizes tested. Solder balling levels appear to be better correlated against the amount of solder paste that is underneath the 0201 component terminations after placement rather than comparing this to th
Electronics Forum | Mon Oct 15 10:51:49 EDT 2001 | davef
On over printing, the general issues are: * Paste deposits being so large that when reflowing, collapse onto many, rather than a single solder mass. * Paste expanding during heating and being close to other solder deposits and bridging [as you say].
Electronics Forum | Mon Oct 22 17:37:51 EDT 2001 | davef
I�m aware of no such standard. There may be something in Euroland [ie, IEC, etc.] TM-650 �Test Methods Manual� has procedures for measuring various types of contamination, such as: * 2.2.25 �Detection Of Ionizable Surface Contaminants� * 2.2.27 �Cl
Electronics Forum | Wed Oct 24 14:06:37 EDT 2001 | mparker
If you let your design team leave things up to chance, chances are something will go wrong. You are right to want to take control rather than be lead down an undesirable path by the fab house. Various masks serve certain desirable purposes. You need
Electronics Forum | Wed Oct 24 18:09:44 EDT 2001 | davef
Allowing the board fabricator to define the board you expect to receive is fine, as long as they do a good job. Regardless of the existence of a clear product definition or not, it�s reasonable for you to argue that your receipts must meet the requi
Electronics Forum | Tue Nov 06 18:39:08 EST 2001 | MikeF
Also, check the website for Assembly magazine, http://www.assemblymag.com, they have some good information on the basics of torque. Determining the "correct" torque value can become very complicated very quickly. The same size screws made from differ
Electronics Forum | Mon Nov 19 20:15:39 EST 2001 | davef
Now, that is one thickass board!!! The rant first: If our �board supplier changed our board surface finish on� anything without our approval, the board supplier would be an �X�. Life has enough surprises. And of all the flat finishes available, h
Electronics Forum | Sat Dec 01 09:09:24 EST 2001 | davef
Sounds like a perfect place to start. Sure we all have different perceptions of fun, don't we? Trial by fire, eh? ;-) A prediction: Your cost accountants are going to freak when they compare the production costs for this board to the more famili
Electronics Forum | Fri Dec 14 13:58:07 EST 2001 | slthomas
This is one I haven't seen before (not in this context, anyway). We have an assembly that we have the SMT done out of house on, because of the high volumes. The boards have two distinct characteristics with respect to the appearance of the solder jo
Electronics Forum | Wed Jan 09 12:20:00 EST 2002 | mregalia
Thanks for cluing me into IPC-2221. Though the numbers they give seem to contradict what I have learned from people working with the materials. At least I now know where the guideline for a max of 30 microinches of gold for soldering comes from. But
