How to remove a lock ring if there is no cassette? A friend tightened the lockring without the cassette on, and now we can't use the chain whip to unscrew it. It's on a road bike wheel if that matters. I'm looking for tools and ideas to undo this. I found this post on a forum, but I'm looking for more answers <

Pad the freehub body with rags, hold it with a big pipe wrench or vice grips.

Another possibility is holding the freehub body pointing downwards in a vice with plastic soft-jaws (or padded with rags, again). If you position the freehub at the side of the jaws you can probably get the lockring tool in underneath.