Electronics Forum | Fri Nov 08 05:08:28 EST 2002 | zolasteven
Can anyone advise on the following : 1. Insufficient pcboard support during printing We are printing on double sided pc boards (approx. 8 ins by 6 ins). There is a problem of high paste when we are printing the second side. The reason bsing the boa
Electronics Forum | Fri Feb 28 08:57:34 EST 2003 | davef
We used to bake [100*C for 6 hours] all of our boards, but no longer bake at all. Before going off, your bake recipe is probaly OK. If anything, it's probably too short. Consider measuring the weight of wet boards, baking for a time, measure, bake
Electronics Forum | Tue Mar 04 12:05:27 EST 2003 | ggspook
Thanks Mike Honestly the whole subject of repeatability is Is confusing i.e. I do perform placement tests using glass plate�s Fuji IP3 and Pam on the Fuji chip shooters which calibrate to 3 sigma but I cannot guarantee placement repeatability As y
Electronics Forum | Thu Jun 26 10:03:36 EDT 2003 | swagner
We have been processing a 3 and 5 up flex array for nearly four years on pallets and have had a pretty steep learning curve. Make sure you have vacuum holes in your pallet for the screen printing process, also work with your support block vendor to
Electronics Forum | Thu Jul 03 12:03:00 EDT 2003 | slthomas
So, there is a crack or gap between: * Solder and component termination. Bingo Correct? Describe: * Coarseness / smoothness of the metal on the termination underneither the crack. * Solder left on the termination. Unfortunately at 45X I can't rea
Electronics Forum | Sun Jul 06 10:07:03 EDT 2003 | MA/NY DDave
Hi Sam, Great answers so far. Let me take a stab at a few of your questions. Q1. whether this is named Pososity? I can't tell from your description. Several companies and the IPC have porosity tests to see if the Gold has good coverage of the und
Electronics Forum | Fri Aug 08 07:52:26 EDT 2003 | pteerink
We have seen this for quite a while too ( chip components and IC's with lead free plating on the terminations ) and we did just what Dave said, crank up the heat. Also switched to newer formulations of solder paste, that are "more active" and have gi
Electronics Forum | Wed Dec 17 09:53:26 EST 2003 | davef
IPC-2222 - Sectional Design Standard For Printed Board For Organic Printed Boards, Table 9-3 � Plated Through Hole Diameter To Lead Diameter Relationships will give you the standard information you require. If we can�t get proper hole fill after try
Electronics Forum | Tue Jan 13 12:43:24 EST 2004 | cyber_wolf
I have to disagree with Fastek. We only use dedicated tooling on our AP machines. Dedicated tooling pros: *Set up time is 90%+ faster than universal tooling. *It is very easy to train operators to install dedicated support plates. *You do not need
Electronics Forum | Tue Sep 28 17:56:02 EDT 2004 | Vee Sar
Adam, I would first check hole to lead sizes on the components that you are having hole fill issues with to see that the spacing is withing spec. Second, check for oxides on lead tips, and contaminated leads that cause poor wetting and insufficient
