Electronics Forum | Wed Sep 19 10:38:58 EDT 2012 | mark25y2001
It's both solderpaste or PCB pad problem... 1st it's possible that your PCB exposure problem or old stocks, remedy? try to bake your PWB. 2nd, it's possible that PWB coating (wax) are more ticked so that solder paste flux are cannot penetrate to clea
Electronics Forum | Fri Jul 06 12:11:34 EDT 2007 | james
We are starting to see issues with using Kester WS R562 with lead free components. The joints look grainy on almost all of the 0402'2 and other small components. Some of the solder does not solder to the terminations. These are hybrid boards which
Electronics Forum | Mon Jul 16 10:17:22 EDT 2007 | realchunks
Yes you can use no-lead parts in a leaded process. Your solder joints will be weaker than they once were unless you change your solder paste. You can try to improve this by running a hotter reflow temp, but be careful since your flux was not design
Electronics Forum | Mon Sep 17 03:59:52 EDT 2012 | stivais
Hi guys, We have an interesting case we haven't seen before (see the picture below) http://postimage.org/image/lu2f4ae55/ Solder balls form on unpopulated pads after reflow. 1. Reflow profile is fine. 2. Stencil thickness / paste volume is also f
Electronics Forum | Wed Dec 22 07:20:21 EST 2010 | piter
HI I used both of solder leveling HASL and ENIG, HASL I can recommended for biger pitch is cheaper solder leveling than ENIG but problem with that solder leveling is during the reflow process HASL isn't flat and during reflow process component move
Electronics Forum | Thu Jul 19 11:59:21 EDT 2007 | hussman
Phil is wrong. In the real world, we know that part mfgers have not changed every one of their parts to make them "high temp". They just changed the plating. Anyone who thinks otherwise, has never run a profile or touched a warm board coming out o
Electronics Forum | Sun Sep 23 18:59:59 EDT 2007 | darby
I presume you are looking at low melting point solders. Firstly, I would consider running BOTH sides with the same paste - this will cut down the opportunities for a mix up with rework or retro-fit. Secondly, check that there is a cored wire availabl
Electronics Forum | Mon Dec 20 16:22:45 EST 2010 | rkondner
When you say Fine Pitch is this .5mm or is it smaller? I wonder what problems they experienced with HASL, the only problem I recall hearing was the surface was not flat. When applying paste with a stencil I can not see how the flatness is an issue.
Electronics Forum | Fri Jul 06 13:44:15 EDT 2007 | shrek
Krikies! seems like a head-scratcher if I may say so me-self. I would say the other ogre is right, that surface finish will play a big factor in your solder joint's grain structure or how shiney 'tis. Non-HASL bearing finishes will typicaly exhibit
Electronics Forum | Tue Sep 11 22:40:26 EDT 2007 | philip_yam
We are testing SAC paste for thru-hole components in the 2nd reflow process. The solder joint is alright but some problem encountered in FR1 or CAM2 PCB after multiple times of reflow due to the temperature. We are very interested in Zn or Bi-based l
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