Can't comment about SMD's but this stuff is great for fixing-up old radios
I have not actually tried it for surface mounted devices yet. However I have been using it for repairing old "tag-strip construction" radios and similar equipment. It is particularly useful for re-soldering dry or broken solder joints. Brush on a little of this stuff, apply a few millimetres or so of new solder and you have a perfect joint, in seconds. Joint is nice and shiny and there is very little residue.
Unexpectedly, I find it quite useful for de-soldering too. Removing a wired potentiometer or socket is much easier if one first coats the joint s with a little of this stuff. The melted solder flows nicely up the solder sucker, leaving the joint clean and making the wire easier to remove from the hole.
I only bought a 50ml bottle because I was not sure how effective it would be. But now I have used it successfully, I plan to order a larger one shortly.
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