I think you hit the nail on the head with this statement. When we changed over to the leadfree stuff, people kept using components designed for use with leaded. THe humble DC socket on a laptop relies on the solder flowing well thro the PTH and filletting the joint on both sides to give mechanical strength to hold it in position. In other words the solder is providing a contact AND securing the component. Leadfree solder doesn't wick up the PTH to the same extent (to any extent?) and so DC sockets fail early. There are several examples of products made around the changeover period that suffered noticable failure rates compared to earlier products.
Hey, I don't mind, it keeps me in business repairing things, I can go "Oh dear, lead free solder again, sorry missus thats going to be expensive!".
Ken
Again, lead free solder will wick along a contact to the same extent as leaded (some types better!), its another lead free myth!
The problem as I have mentioned before is that lead free solder requires about an extra 15 degC to flow properly when compared to leaded. Trouble is that on some of the units on change over, they had a mix of components some of which would not tolerate the full extent of the required higher flow temp so a compromise was to run 5 degC or so below the optimum for a slightly longer period and the result is that the lead free solder does not flow so well.
Again, nothing to do with lead free solder which is excellent and evidence now sudgests, better, when used correctly.
What you should be saying is 'ow dear, poor manufacturing procss again'
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Topic: Met my match SM PCB (Read 1167 times)