wrote:
I'm trying to wash off some copper sheets I've soldered together with
lead-free solder. I used Oatley #95 lead free tinning flux and I tried
to wash it off with strong detergent but no luck. Does anyone know an
efficient way to wash this stuff off?

MSDS indicates negligble solubility in water but base is 60-70%
petrolatum so I'd try a petroleum solvent on a rag. Might check on
www.oatey.com to see if any further information (btw, note there's no
"L" in "Oatey").