Electronics Forum | Tue Aug 08 21:00:24 EDT 2000 | Dave F
Shawn: You're correct most solder preform manufactures don't want to sell preforms without skinning you alive for tooling charges!!! Considering alternatives, can you print or dispense paste? It would be mucho cheaper. We've talked about using pa
Electronics Forum | Wed Sep 15 22:52:58 EDT 2004 | pdeuel
We had same problem. Solder balls appeared on top side of board and led to damaged second side stencles. We worked around problem by running blank boards thru oven and inspecting and removing solder before processing boards with parts.
Electronics Forum | Sun Aug 15 05:45:15 EDT 1999 | Brian
Boca, Dave Sorry, but I cannot let this go. I'll go along with you that, at the time that the Montreal Protocol was initially signed (September 1987), there was no scientific proof that CFCs etc. were causing ozone depletion. There was, however, ve
Electronics Forum | Tue Sep 14 14:52:22 EDT 2004 | Carol
During processing, the solder in the vias reflows and forms solder balls. PCBs have solder in random PBGA vias from the board manufacturer.The manufacturer says this is a result of the HASL process and is unavoidable. We use HASL finish, multilayer,
Electronics Forum | Mon Sep 29 14:47:15 EDT 2008 | davef
Let's narrow this down. Questions are: * Are you putting the proper amount of solder in the board with your stencil print process? * If you are putting the proper amount of solder in the board, where is the solder going? Pick one and then fill-in th
Electronics Forum | Wed Apr 28 22:35:32 EDT 2004 | davef
We can clean the blank out of LARGE BGA. [Cleaning small BGA is a whoooole nuther issue.] But before we get into that, what's the problem and its breadth? Why are you getting poor wetting? What's the story on the components, board, process materia
Electronics Forum | Tue Feb 25 10:30:02 EST 2020 | richardcargill
If you get the stencil made with all apertures included then you can blank some off with sellotape. Saves you buying 2 stencils should you require them machine fitted in the future
Electronics Forum | Thu Nov 10 10:15:40 EST 2011 | davef
J-STD-003 describes the test methods and gives guidelines for assessing the solderability of bare circuit boards
Electronics Forum | Thu Nov 10 09:25:54 EST 2011 | kevinemslie
We have had an issue where a turnkey company has a solderability issue with boards that we supplied. The most thorough way of proving thay the boards work in my opinion is to take a bare panel randomly from the batch (same date code) to have it paste
Electronics Forum | Mon Mar 12 13:57:50 EDT 2007 | davef
That your problem is not related to component solderability or wave process related makes us believe this has to do with bare board design. Look at how your designer did the thermal relief on the two pins that don't solder well. If you can't get a
