Then using some fine wire wool rub gently over the grout which will begin to dissolve and rub off at the same time.
Removing old grout from wall tiles.
Allow the tiles and grout to completely dry.
Make sure to apply enough water that it can soak into the grout for an hour or two before you try to work any of the grout off.
Remove a piece of tile from the solution.
Tape the tiles so that the grout joints are all that is visible.
Taping will help to stop you from sawing into the tile as you cut up the grout.
Fit the oscillating tool with a blade specially intended for removing tile grout.
Once the tile is clean and has no more hardened grout wipe over with a damp cloth and leave to dry.
Use the scraper to clean off large debris and then clean off any soapy residue with a damp cloth.
Take one gallon of warm water and dissolve a cup of sugar into it.
Remove the grout from between the pieces of tile with a grout scraper using the incision as a starting point.
Take the water and sugar mixture and pour it over the grout that needs removed.
Take this sweet solution and pour it onto excess grout on a floor.
In concert with the grout float a large damp sponge.
To do this use the grout float again this time holding the tool at an 80 degree angle to skim the excess grout from the face of the tiles.
Using a wooden paint stick gently scrape at the grout removing the larger chunks from the surface of the tile.
Keep the tile wet with the sugar water for at least two hours.
The basic method for hardened grout removal use warm water and wipe it over the surface of the tiles with a sponge.
Apply firm pressure and drag the scraper along the grout line about the length of one tile but be very careful to avoid scraping the tile.
Insert the triangular tip of the grout scraper into the incision you made with the grout saw.
Scrub the mortar with a scrub brush to remove the residue the acid has loosened.