On Sun, 15 Jan 2012 16:03:19 -0800, "walter"
wrote:

I have a tile patio with 1/4" grout lines between the 16" tiles.

In a few places, the grout has cracked and disintegrated, probably due to
thermal expansion.

Prior to replacing the grout, what is the best way of removing the remnants
of the grout from the spaces between the tiles.

Somebody suggested the HF Multifunction Power Tool ($ 19.99). Would this
work? Any betters suggestions?

Thank you

Might do, but 1/4" is pretty wide and a patio is pretty big.
If it's a small section, a hand grout saw will do.
If I was re-grouting all of a patio more than about 10' square, I'd
use a circular saw with a masonry blade.
Have to carefully set a guide, and best to have a vacuum attachment.
That would be fast.
Never did it, mind you, but I've cut pavers that way.
I'd use a straight 2x4 or angle iron as a guide with sandbags keeping
it in place. Don't want to hit the tiles.

--Vic