I have just regrouted a large floor, i was doing about 10 metres aday using a fein multimaster with a carbide blade. the tiles were 600x300 porcelain with 4mm joints, the fein works really well and didnt chip any of the tiles, hope this helps
i had the same problem on the gray b&q tiles. i used a aquamix cleaner and alot of elbow grease, they came up really nice. you can buy it from trade tiler, theres a link to the web page in the forum sponsors :thumbsup:
