Waterproofing Your Stained Glass Stepping Stone

While DiamondCRETE makes a waterproofing substance, I’ve never used it, so I can’t say how well it works.

I can say, however, that I have used Ducksback Waterproofer by Masterchem and love it. It’s available at any home improvement center or hardware store. It is a water-based product specifically for heavy duty concrete and masonry. It penetrates the stone, it doesn’t turn yellow, and it works. When brushing it on your stone, try not to get too much on the glass. And just be sure to wipe the glass immediately after getting it on there. It doesn’t really hurt it, but it makes it a little filmy and then you’ll have to scrub it off later. Catch it early and save yourself some work. Your brushes will clean up with soap and water.

Treat your stepping stones to this waterproofing once a year.

Removing Your Stone from the Mold

When the stone is ready to pop out of the mold, find a surface to place it where it won’t be disturbed. Lay some pencils down where the stone will cure. You’ll place your stone on those pencils which will allow air to flow under the stone and help it in its final stage of curing and drying.

Carefully turn the mold over and set it on the pencils. Then lift the mold. Your mold will probably come right off with little trouble. If it needs a little coaxing, press on the center very gently.

Immediately peel off the resist and wipe the glass. Sometimes the DiamondCRETE will seep under the edges of the resist a little bit, but this is not a problem. Just take a rag and wipe it away. Get the glass cleaned off real well. Then inspect the surface, especially between the pieces. You may notice a few little holes where air got trapped. Simply take a teaspoon full of dry mix, add a few drops of water to get a good consistency, and fill the hole. Wipe the stone smooth. That should do it!

Let the stone continue to cure undisturbed for a full month. After that time, it will have reached its full strength and will be ready for waterproofing.

Cleaning Up While the Stone Cures

While the stone is curing, you can clean up your mixing bucket. Don’t clean and then pour into your plumbing system because it is, after all, a form of cement, and it can really gum up the works. You can allow it to set up and then break it out of the bucket later, but I always found this to be difficult. My favorite way to clean my buckets is to fill them with water and let them soak for a good long time. The concrete will settle to the bottom but won’t harden, you’ll be able to pour off the water, and you can wipe the sand and grit out of the bottom with rags or paper towels. Works like a charm!