Electronics Forum | Mon Nov 14 10:45:05 EST 2005 | kmeline
We seem to be having a lot of issues with solder not flowing to the end of surface pads especially on fine pitch. These are assemblies we have run in the past with few issues. The bareboard finishes do not look the best. Has anyone been experiencing
Electronics Forum | Thu Jun 26 07:44:07 EDT 2008 | kmeline
Hello, we are having issues with two assemblies where the Melfs will lift or not solder on one end of the components. Has anyone had issues with this in the past? What can be done to help this? Thanks
Electronics Forum | Thu Jun 26 09:09:27 EDT 2008 | kmeline
The pad size is okay. I have also requested the manufacturer's recommend reflow profile. I have seen some issues with 0402 caps that we run also but for the most part solder paste does okay. I think the cap issues is stencil related. Still trying to
Electronics Forum | Thu Jun 26 09:47:12 EDT 2008 | kevinjm
Hi Mark, Are these lead free parts on a leaded process? If so, that could be your problem. We had the same issue in my place a while back.
Electronics Forum | Mon Nov 14 12:23:56 EST 2005 | russ
What is the finish of the PCB? What type of paste are you using?
Electronics Forum | Thu Jun 26 08:20:42 EDT 2008 | cyber_wolf
Check your pad spacing on the board. Look at the IPC specs for pad design.
Electronics Forum | Thu Jun 26 09:33:11 EDT 2008 | realchunks
Yes, try slowing it down. It will indicate if your ramp up is too fast.
Electronics Forum | Thu Jun 26 09:42:16 EDT 2008 | gabriella
Hello Mark, I would recommend to look again on the pads. in many cases board design is causing these issues. Check 1. Is pad size good for the part 2. Are both pads the same size 3. traces connected to the pads should be same size 4. vias connecte
Electronics Forum | Mon Nov 14 14:59:32 EST 2005 | davef
Additional questions are: * Does the problem appear with pasted/soldered only boards, in addition to those with components? * What is the size of the unsoldered area? What is the size of the pad? * Where is the solder mask, relative to the pad? * Wha
Electronics Forum | Thu Jun 26 07:53:39 EDT 2008 | realchunks
Depends on a few variables. Could be the part, your profile, your paste, your stencils..... many things affect it.
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