Hi all,
I know there are other threads that have already discussed these matters, but they don't seem to answer my questions, so I've started this thread. I have two situations where I need to mix leaded and unleaded solder and would like opinions on any issues I might encounter.
Situation one is repairing modern equipment. I prefer hand soldering with leaded solder (for numerous well known reasons). I have a repair where removing the lead-free solder isn't really an option, it's a massive connector 100+ pins and to fully remove the old solder I'd have to unsolder the entire connector, when the repair only requires resoldering 4 or 5 pins.
The other situation is a batch of PCBs, where the SMD components were reflowed using lead-free solder. Several other parts (connectors) need to be added by hand, but the lead-free solderpaste was applied to those contacts too.
Do I really need to remove all the unleaded solder? Are the issues I've read with cracking / blooming etc really a problem?
McBryce.
P.s. As my "normal" electronics activities mainly involves repairing equipment from the 70's and 80's, I don't currenty own a reel of lead-free solder and would prefer not to have to buy some if possible.