I recently noticed the caulking between the counter and the backslash in the kitchen needed replacing. This happens. If you don't stay on top of this, water can get behind the counter and cause problems.
Tools:
one sided razor and holder
rags
masking tape
scissors to cut the tip of the tube of caulk
new caulk the color of the old caulk, I needed clear silicone
First you have to clean out the old caulk. This takes a one sided razor and patience. You want to scrape off the old caulk, not scratch the granite, so hold it at an angle and scrape gently.
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Doing this behind a faucet is a challenge. I had to take the razor out of the holder and contort my hand to get the job done.
Clean and dry the surface.
Carefully place the tape above and below the gap you are trying to fill. The easiest way to to this is to hold one end of the tape on the surface below the gap. Unroll about six inches.
Raise and lower the free end until it is exactly where you want it and press it smooth.
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Repeat this until you get to the end of the project and then do it again above the gap.
I didn't have a large area to fill, so a small tube of clear silicone caulk worked for me. If you have a larger job, a caulking gun and tube are better.
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You can see the detailed instruction were very helpful....if I could read them, the print was VERY small.
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It was also particularly helpful to have the cat lie down right behind me.
Squeeze the tube as you fill the gap. Get eye level to make sure you are using enough. I had to go back and add caulk in a few places, like in the above picture
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Don't worry if it is a bit lumpy, although you should try to do an even bead. I couldn't get close to an even bead behind the faucet. After you finish, get your finger damp and run it gently along the bead of caulk to smooth it out. If you put way too much caulk, you will have to stop and wipe off the excess. Then wet your finger again and continue.
Let the caulk dry for about 10 minutes and then remove the tape. You don't want to wait too long as the tape may then pull out some of the caulk. Pull it at a sharp angle away from the hole to break the connection with the tape. It may not be as smooth as you like, mine wasn't, so wet your finger again and make one more pass over the caulk.
Wait for it to dry according to the very tiny instructions and you are back in business.
By the way, the cat wants a treat. He did help, after all.