Over a period, the sealing material between my tub (fiberglass I think) and my sheet vinyl flooring has gotten ugly. It's still water tight, but very uneven. I'd like to remove the old stuff and replace it with a neat bead of clean new stuff.

How to remove the old caulk has me beat, I tried a putty knife and failed. Would it damage anything if I tried to soften the old caulk with a hair dryer before prying it out?

I don't think applying heat will soften it enough to remove it. If it's still holding water why not do what we do and run a thin layer of White Dap Tub and Tile Caulk over the joints. Good luck, Tom

At most home improvement stores you can find a caulk removal tool (look in the paint dept) which will allow you to pull the old caulk out, and replace it with a new bead. We've done this before with our tub, and it works quite well.