worktop radius

[jonny round boy]

From your description, you've basically got this:



And you need to add a curved fillet like this in red:



Trouble is, if you just add it like this, you'll have a problem with the 'pointy bits' at the end of this piece which could easily break off. Plus, it'll look crap.

What I would do is add a new piece to the breakfast bar, glued & biscuitted to essentially widen the b/bar:



You can then cut the curve into this, and then butt-joint the 600 piece to it as normal:



Is that what you're looking to do?