I have no clue. I think, maybe, there is a special tool for grout
removal. You might call a tile store.


Mark wrote:

"Sleepy-Tom" wrote in message
u...
Im replacing the tiles in my bathroom and i have cast iron enamel
bathtub with old tile grout and mortar mix on the top edges.
Ive tried using warm soapy water and a nylon brush but its not coming
off.

Whats the best way to remove this old grout/mortar from the enamel
surface without scratching it?

If soap and water would wash grout away it would have done so long ago.
Grout, particularly the older stuff, is largely portland cement. Once
it's dried and cured there isn't much that will cut thru it that
wouldn't also damage the enamel on the tube. Your best bet is to scrape
at it gently with a tool designed for this.

Another thing to consider is where your new tile and grout will fall. If
it will cover the old, then I wouldn't waste the time cleaning it
completely, just where it may interfere with the new installation