This is a method for direct mosaic stones that was posted on the WC glasschat forum by Denise (djd), I’m sure it will be a great help to us all. Thank you, Denise.
“I have been making stones using the direct method for about 4 years, and they turn out great. I’m not an expert and I’m sure my way isn’t the only way, but it works for me maybe this will help you too. Good luck and have fun!”
- Ready made stepping stone
- Ceramic tile adhesive
- Grout float or rubber scraper
- Small notched trowel or comb
- Masking tape
- Latex additive
- Sanded grout
- Stained Glass
Purchase ready made stones from any home improvement or garden store. They usually have small rocks embedded in one side so you will be using the smooth side. Be choosy when picking your stones, sometimes they have chips broken off the top edges (they will work, but you will need to fill with more grout).
I use a sealer on my stones and pots and other mosaics before and after attaching stained glass to them. I’m not entirely sure that the stones need to be sealed before, but terra cotta pots, wood and most other surfaces definitely need it. I just do because it’s easy, cheap and gives me piece of mind.
The pattern should be 1/4″ to 3/8″ smaller than the stone you will be using. When cutting out the pattern you will want to have at least 1/8″ gaps between the glass pieces. If your pattern does not cover the entire stone and you will be using scraps to fill in the background, the grout will fill in easier if there are not wide gaps between the pieces (it can be done with up to 1″ gaps but will take more than one application of grout).
After cutting all of your glass pieces there are 2 different ways of attaching stained glass to the stone:
- The first is to “butter” each piece with tile adhesive, then place on stone or pot. I do it this way when I draw my pattern lines on the stone or I am making a mosaic pattern with random pieces and it is a large stone, bird bath or a clay pot.
- The second way is to apply the adhesive directly to the stone. To do this you will need to make a copy of your pattern reversed (you can just flip your pattern over and redraw the lines that you can see them through the paper). Next, lay a piece of clear contact paper on top of the pattern (sticky side up so you can see the pattern through the contact paper). Position the glass pieces onto the contact paper. Use a notched trowel to spread the adhesive evenly over the stone (you can also use a wide tooth comb or one that has every other tooth removed). Carefully flip the contact paper with the glass pieces stuck to it onto the stone. Placing your palms on the contact paper and stone press & wiggle the pieces down to the stone. Let the adhesive dry at least 24 hours before removing the contact paper. After removing the contact paper make sure the adhesive is completely dry before grouting, sometimes it takes another day to dry without the contact paper on it.
Masking tape is used to make a form, so to speak, around the stone so that the grout doesn’t spill off the edge and to make a cleaner looking edge. Just attach it to the edge about 1/4″ down all the way around the stone.
I have used both un-sanded and sanded grout for my stones. I like the way sanded grout goes on better, even with larger spaces I rarely have to go back to apply a second coat, as I almost always do with unsanded. However, I think most people use the unsanded for fear of scratching the glass. I personally have not had a problem with scratches. In Minnesota, with the drastic changes in temperatures, I find that it is a good idea to use a Latex Additive instead of water to mix my grout. I have never had any glass crack in my stones and they stay outside all year. Follow the grout mixing directions that are on the package with the exception of using the latex additive rather than water. Mix to the consistency of peanut butter or toothpaste. Be very careful to not breathe in any grout dust, It’s extremely bad for you. As far as how much to mix, I don’t know, it all depends on the size of the stone, size of gaps, size of pieces etc. I usually end up mixing up too much but then I have some left over if I need to fix any areas. With the grout float or rubber scraper, spread a generous amount onto the stone working grout into the gaps and up to the masking tape on edges. Apply in a diagonal direction across the gaps to prevent the grout from being dragged out of gaps. Go over each area several times from all directions to make sure that the grout is fully packed in. Remove any excess grout from the surface by holding the float at a 90 degree angle to the surface and moving it diagonally across the gaps. After removing excess grout from the surface, allow the grout to firm up for about 10 minutes (½ hour if using water rather that additive). Remove masking tape from the edge of your stone. Wet a sponge in cool water and wring out all excess water. Wipe the surface of the glass & grout lines in a diagonal direction. This will remove remaining grout residue and smooth the grout lines. (Be careful not to rub too hard because you will remove the grout from the gaps and have to start over). Continue doing this making sure to rinse the sponge frequently until the glass is fairly clean. To smooth the edges, carefully wipe, following the edge of the stone with sponge. Wait about ½ hour and repeat the cleaning process. After the grout is dry you can polish with a dry rag to remove the haze left on the glass.
I usually wait at least 3 days before I seal the stone. Make sure you seal all sides if you’re using it outside.