Seems like there have been several threads recently regarding stuck faucet handles, etc. Just a solution for a problem I had over the weekend in case somebody comes along and googles...
Single lever Delta lavatory faucet needed replacement seats/ball to stop a drip. We have very hard water and the handle was not possible to get off even after letting sit w/ a modified baggie full of vinegar and CLR around it over most of two days. Didn't dissolve enough of the calcification even w/ the set screw out as an access point, surprisingly.
Solution was to take a piece of 3/4" thick hardwood about 3" by 8" and drill a 5/8" hole in the middle. Then split it lengthwise and placed it around the handle behind the knob on the end and used a small C-clamp to hold it in place. This provided a good surface against which to use a hammer/mallet while applying pressure on the other end.
Took a surprising amount of effort w/ the hammer yet, but removed the handle w/o damaging any of the plating, etc.
HTH somebody, maybe...
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