Electronics Forum | Fri Aug 01 02:10:26 EDT 2008 | fowlerchang
Pad design is not only the size of pad but also the distance between two pad. N2 will increase tombstone as we tested. 10 zones reflow oven and slow temperature ramp will reduce this defect. MustII is the equipment which is used to test the solderabi
Electronics Forum | Fri Aug 01 00:22:46 EDT 2008 | fowlerchang
Pattern design, paste volume,printing misalignment, place misalignment,reflow process include N2 usage. All the factor above can make tombstome happen. And the most important factor is placement misalignment except design issue. But pls check the sol
Electronics Forum | Fri Aug 01 00:40:06 EDT 2008 | roc2x
thanks,my pad design is 24 x 23 mils and now I chnged my stencil to 24 x 20 mils ship inwrds to lower down my volume. My placement is and part data are ok. My reflow N2 is using 1000ppm, Actual is 700-800ppm I already prolonged my pre-heat butit only
Electronics Forum | Thu Aug 24 09:41:46 EDT 2000 | Dr. Ning-Cheng Lee
The optimal profile to choose is determined by the following factors, (1) thermal mass and distribution across the board, (2) reflow temperature range needed for a particular alloy, (3) the nature of flux. When the thermal mass is small, such as cell
Electronics Forum | Sun Mar 20 12:58:23 EDT 2011 | sellenzz
We have a Nitrogen Silo. Your going to want to be careful if you decide to use nitrogen, not only are the levels unstable most of the time but it can also cause your components to tombstone like crazy, especially if you run a lot of LED's. We run 24/
Electronics Forum | Tue Sep 09 12:05:44 EDT 2008 | tonyamenson
First and fore most is to find your paste manufacturer spec sheets. Read it over several times and let it all sink in. Then call them with questions as they want to keep your business so their engineers want to help you use their product. I assume y
Electronics Forum | Mon Apr 09 20:55:46 EDT 2012 | action_101
I forgot to add that we are using a 3 mil stencil. It seems like to me that may be there isn't enough flux left when we reach liquidous?? About half of the solder spheres do melt and wet on each pad, but the top half of each solder joint is just the
Electronics Forum | Mon Sep 11 14:58:16 EDT 2006 | cuculi54986@yahoo.com
Steve, Let me guess, you were using this one: http://www.panasonic.com/industrial/components/pdf/abd0000ce10.pdf That part sucks. They have a newer part number that is supposedly "reflow-friendly". Unfortunately, I can't convince our quality de
Electronics Forum | Fri Sep 08 09:16:37 EDT 2006 | james
We are incurring problems with Film Chip Capacitors with reflow issues. Some of the parts are misaligning or not soldering on one end (almost tombstoning) . We left the parts in the dry cabinet till they were used. We tried both reflow ovens (hell
Electronics Forum | Mon May 22 15:46:49 EDT 2006 | adlsmt
Grant has a good idea, we started that way also. We made a tank out of stainless steel with copper tube coils about 18" off the bottom. Circulate cold water through the tubes to condense the vapor to keep the loss down. We used electric burners under
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