corrosionfaucetkitchen-sink
I am trying to replace my kitchen faucet but the nut holding it onto the sink is corroded and the nut won't budge! I have tried a basin wrench (as someone suggested here), wd40, hammering at those notches with a screwdriver and am not getting any movement. How can I get rid of this faucet? I don’t mind destroying it as I have a replacement already in hand.
The next step secret to getting more of this faucet apart are the two slots cut across the cupped part. See the arrows in the following picture.
It looks to me as that the cupped part is threaded down inside the larger diameter part that sticks up from the hole in the sink. There is probably a special tool used to engage these slots to thread the part out. It may be possible to lay a piece of metal bar stock across these slots as a tool. If you do that make sure that it has nice square corners.
What you're after is a tool called a basin wrench:
It can reach up behind the sink and tighten those nuts.
Best Answer
As somebody in your other question noted, you probably have to attack this from the top. A hacksaw will be time (and arm) consuming. An oscillating multitool with a metal-capable blade would be good though slow-ish. An angle grinder would be fast but will also throw sparks and has the non-trivial risk of having the grinder catch and run into stuff you don't want ground, like the backsplash.
Alternately, you might try to drill out a weakness in the nut with either a large drill bit or linked smaller ones. That would allow you to pry it loose.