Electronics Forum | Tue Sep 24 12:49:43 EDT 2002 | dragonslayr
Aperture reduction @ 5 mils thickness is your best bet. It may take several attempts to get just the right paste volume. What aperture reduction was specified to the stencil house for these specific LEDS? or was the stencil blindly produced using a
Electronics Forum | Thu Nov 02 09:45:00 EST 2000 | bierleinb
I would check trace-pad interactions as you may be robbing heat from one of the pads causing uneven heating during reflow. Also, measure paste deposits on trouble parts to see volume depsoted across the pads. You should easily be able to do 0402s w
Electronics Forum | Thu Aug 15 15:44:46 EDT 2002 | dragonslayr
You can't control what you don't measure. You have provided very little detail other than post reflow costs are high. What defects are attributed to problems experienced prior to reflow? Are these random or recurring defects? You will need to put ea
Electronics Forum | Tue Oct 26 02:22:51 EDT 1999 | Joe
dave: One more thing about dpmo, I should have mentioned before is, how do you measure dpmo in your production? About the post print inspection, how do I measure paste height? (I have a microscope, will this do?)
Electronics Forum | Fri Jan 05 19:47:08 EST 2001 | slowe
Hey everyone, Does anyone out there use a solder paste height measuring system ? I would like to know what the standard is for paste height compared to stencil thickness and how you use it as a process tool. I appreciate any help. Thanks, Steve.
Electronics Forum | Sat Jan 06 10:37:43 EST 2001 | Dave F
We have talked about using mircoscopes and laser thingies for measuring paste height on SMTnet previously. [Fine SMTnet Archives might give background.] Some people use a 0603 chip cap as a standard. I'm not sure how stencil height relates. Paste
Electronics Forum | Tue Oct 26 13:57:34 EDT 1999 | Dave F
Joe: Both dpmo and measuring solder paste height are good topics to practice your SMTnet archive searching skills. Yes, some microscopes can be used to measure solder height. Good luck Dave F