Replace grungy, eroded grout in your shower. Simplify the tough grout removal part with an inexpensive power grinder. It speeds up the job so you can move on the easier parts, regrouting and polishing the tile.
By the DIY experts of The Family Handyman Magazine:September 2001
Attach the removal unit and set the bit depth to 1/4 in. Run the tool guides between the tiles and grind through the old grout. Clean joints with a grout saw.
Renewing old grout has always involved long hours of hacking away at old, worn grout with a tiny grout saw. Simplify the job by purchasing a grout removal kit that attaches to a Dremel tool. (See photo below). It has a high-speed carbide bit that effortlessly chews away old grout, and guides that keep you from chipping the tile edges. Make sure to wear safety glasses while grinding (Photo 1). Use the grout saw to scrape out edges and corners and to clean out the joints.
A grout removal kit contains the grinding guide and a grout saw for cleaning along edges where the grinder can't reach. It's designed to fit a Dremel tool.
Using a grout float, push the grout diagonally across and into the vacant joints.
Vacuum up any dust or debris left after the grinding process. Take a chunk of your current grout to a home center or tile shop to find a match. Also buy a latex additive to mix into the new grout to make it more durable. Mix the grout slightly thicker than peanut butter and then apply it (Photo 2).
Wipe the excess grout and film off the face of the tile with a damp sponge, rinsing it often.
When the film reappears, buff the entire area with a dry cloth.
Let the grout set up for approximately 20 minutes until a film develops over the tile, then clean the area as shown in Photos 3 and 4. After the grout has dried for a week, protect it with a grout sealer.
Have the necessary tools for this DIY project lined up before you start—you’ll save time and frustration.
You'll also need a sponge, a grout removal kit, a grout float and rubber gloves.
Avoid last-minute shopping trips by having all your materials ready ahead of time. Here's a list.