Electronics Forum | Tue Aug 22 10:57:48 EDT 2000 | caumel
Hi folk's With some pcb's after wave soldering ,we find some solder blobs on vias. There seems to be air inside these blobs What can we check in order to solve this problem? Thanks in advance
Electronics Forum | Tue Aug 22 14:02:02 EDT 2000 | JAX
Caumel, You should be able to find sufficient info in the archives. Solder Balls probably hold the majority of posts and should be easy to referance. You can find out what causes them in relation to board material, profile tempature, wave type, flu
Electronics Forum | Tue Aug 22 14:52:55 EDT 2000 | John Thorup
Jax - absolutely right - the archives are a valuable tool and deserve to be used more than they seem to be. Caumel - Are your blobs on the solder side or the component side? Are your vias tented on the component side? What size are your vias? Is th
Electronics Forum | Tue Aug 22 19:47:57 EDT 2000 | Dave F
No you're NOT, Jax, you�re 100% correctamuno!!! Thanks for setting-up the soap box. I believe that responding to repeated questions other than referring the person to the archives degrades the Forum. This Forum is pathetic in its pandering to peop
Electronics Forum | Tue Apr 28 14:03:03 EDT 1998 | Achim
We want to produce BGA�s which will be see burn in conditions of 140�C / 24h active tested. Now we think about problems for the solderball uniformity. Does anybody know about problems or about special solderball alloys for such productsconditions ?
Electronics Forum | Fri Sep 22 13:59:40 EDT 2006 | realchunks
Be careful of inverted homeplates if you hand clean your stencils. The "spikes" can easily catch on the wipe being used and bend up. Not to mention the nice slashing it does on your hand that immediately some how fills with solder paste.
Electronics Forum | Mon Sep 25 14:57:02 EDT 2006 | jaimebc
For this inverted homeplate, the edges are rounded vs. spikes. Check image here : http://www.emasiamag.com/article.asp?articleid=669
Electronics Forum | Mon Sep 25 15:13:57 EDT 2006 | realchunks
Yup, seen them too. Be care not to apply too much squeegee force or you could start to see these curl up as well.
Electronics Forum | Mon Sep 25 17:02:42 EDT 2006 | jaimebc
Thnaks for the tips so far. I am currently reading our paste manufacturer's procedure for handling solder paste. I will try to adhere to it and control our old vs new paste.
Electronics Forum | Tue Sep 26 10:39:35 EDT 2006 | aj
Just to update you on what I have found. I was using Indium leadfree paste and I switched to Alpha OM338 Leadfree Paste. Problem gone...no more MCSB. aj... I have no affiliation with either ofthe above mentioned companies.
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