Sheldon has been using the Chipquik SMD291NL no clean tack flux, here is his review of it:
Very tacky, can hold qfn and dfn by itself, once heated it becomes very sticky and is hard to clean even with 91% ipa.
It works great though, have not had any problems with it not wicking solder under tight parts.
Overall it is an ok product, was meant for the chipquik remover system, but is sold by itself.
8 out of 10
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