Fred "Fred" Fred wrote:
Need sage advice on how to removing an old leaking hot water shut-off
valve and salvage the nut. Can't budge the nut and has bimetal
corrosion. Would anything work better than std penetrating oil or
WD40?

Normally I would cut the pipe and install new nut, etc. Long story,
but the pipe is inaccessible from both sides of the wall. Old
built-in vanity cabinets - big project to move. Can reach the nut &
valve with wrenches but not with saw or pipe cuttter without tearing
out the cabinet.



PB Penetrating Catalyst, in the yellow spray can at your auto parts shop.

A twenty-year supply costs about $3.00. The can will never go empty because
you don't use much.

Honest-to-God, it's good stuff !