Sunday, March 22, 2009

How to Make a Poured Concrete Stepping Stone

Half of our yard is covered in river rock. Not easy to walk on. I've decided the solution is MANY stepping stones- guessing about 50. I could just buy a bunch at the home center, but what fun is that?? Instead I'm making poured concrete stepping stones with a different mosaic design in each. I have a few already made and thought I'd share the process I've been using. You can make these mosaics as simple or as detailed as you desire. I'm planning on using up a whole lot of bits and veering toward the simple end.

Some supplies you'll need or just find handy:

  • Portland cement type I
  • Sand
  • Dish pan (dedicated) for mixing in
  • Some sort of trowel or small hoe as a mixing tool
  • Some sort of disposable, or never to be used again for food, cup for scooping sand and cement.
  • Clean water for mixing (or admix of some type if you live in a frost zone- read labels at your home center to find an appropriate admix).
  • Disposable dust mask. Very important to wear this while working with the dry cement!!
  • Hardware cloth
  • Wire cutters or similar for cutting hardware cloth
  • Gloves- heavy duty for use when cutting hardware cloth and vinyl disposable for when mixing concrete.
  • Mold. For this project I use a 14" diameter commercially made stepping stone form.
  • Clear contact paper
  • Some sort of tesserrae for piecing a mosaic design. I use stained glass frequently.
  • Mold release of some sort. I use petroleum jelly- cheap and easy to find.
  • Newspapers for work area
  • Plastic to cover concrete after unmolding.
  • Sturdy board larger than the mold to use when flipping the mold in step 6.

***In addition to the instructions below, please also see the comments below this post!



1. The mosaic design is pieced in reverse on the contact paper. Place the mold on the paper side and trace it then cut the shape out 1/4" inside the line so it will fit inside the mold. You can sketch out a design on the paper portion. Peel off paper, and place sticky side up on your work surface with the design underneath. Remember to reverse words/letters/numbers so they are mirror image while piecing.






2. Figure out how much sand and Portland cement you need. For this project I use recipe #3 in the book Making Concrete Garden Ornaments by Sherri Warner Hunter. One great tip, among many, from this book is to fill your mold with sand and measure the volume. This will be how much you use for the project and 1/3 of this volume is how much Portland cement you will need. Use approximately half as much water/admix as cement by volume. I have a wonderful old clear plastic pitcher with very straight sides that I have marked this ratio on for each mold size I use.





3. Smear a thin coating of petroleum jelly on the inside of the mold. Place the contact paper/pieced design into the bottom of the mold with the pieced design sticky side up. Use the wire cutters to cut a circle of hardware cloth about 2" less in diameter than your mold (one inch smaller each side).







4. Add the sand to your plastic bin. Put on your mask and measure out the Portland cement and add it to the sand. Stir in well and slowly add in water/admix in increments. Be real careful that you do not add too much liquid. I aim for a very soft cookie dough consistency. Not crumbly but never runny.







5. Go slowly adding the cement mix to your mold. You need to press the concrete into all your spaces but carefully so you do not dislodge your pieces from the contact paper. Fill the mold half way then place in the hardware cloth piece. Raise slightly and tap the mold down to the ground repeatedly to raise any air bubbles. Fill the mold the rest of the way and repeat the tapping to again remove air bubbles. Smooth the surface. Clean up plastic pan and tools OUTSIDE. Cement/concrete washed down a drain will harden in the drain!



6. The filled mold needs to sit undisturbed until the surface is firm and no indent is made when touched. I found the amount of time this takes depends very much on the air temperature. In the summer here (90's day 70's night) it required only six hours but in our current temps (70's day, 50's night) it takes 12 hours. When firm enough, gently pull mold away from sides very slightly. Place a stiff board (I use a leftover large floor tile) on the stepping stone surface and carefully flip the board and the mold. Slowly pull the mold straight up to remove. Remove the contact paper slowly. The surface can be gently cleaned using a paper towel or a piece of newspaper. ****If you have small air pockets visible and would like to fill them in, mix together a slurry of just Portland cement and water. You can then use this to fill in the divots. Work a very small area at a time!! Cover in plastic and leave undisturbed for at least three days. After seven days it will be cured enough for walking on and the color will lighten to about its final color.













Interested to see what else I've done with stepping stones? Click here to go to all posts tagged with 'stepping stone'. All designs are my own. If you make some stones I hope you use the opportunity to also create your own designs. Have fun!

I don't just play with concrete!! 

See my Etsy MosaicSmith shop for available mosaic art.





11 comments:

V said...

Thanks for the clear instructions and photos. I'm creating about 20-25 stones for my yard and I've only used Quickcrete in the past(expensive!).
Your tips for using the Portland cement should save me some money and the adding of the wire should help them survive the perils of the yard!

trish said...

your instructions were easy and your project looks great..hope mine turns out that good...
Trish

Lori Jo said...

Thank you for your "how to" it was the first one I found that made sense. I can't wait to get contact paper and get started.

Linda Smith said...

I am so glad you all have found this post helpful! I'd love to see photos of any stepping stones made using this method. And if you have any tips after using these instructions, please let me know, thanks! (Follow links <== to e-mail.)

Christine said...

Hello Linda,

I finally made a stepping stone last night. I have made s.s. in the past, but I buy the pre-made ones and glue and grout the tiles. I did make the mistake of not pushing the cement in and picking it up and kind of tapping it back down (for air bubbles) First one, won't be perfect. My question is I use the ceramic tiles. You can't see the colors of the tiles too well. I did make a template of the bottom of the mold pan and made a pattern. Then I transferred them (upside down) onto the contact paper. But if I am doing really detailed things, how do I keep it straight? I thought I could put them together and then take the contact paper and place it on top of the tiles, but they would move around too much. Any suggestions? Thanks so much for sharing your ideas with everyone. Christine

Linda Pieroth Smith said...

Hi Christine, Ceramic does make it more challenging. If you are using contact paper that is clear, you could color your pattern and place it under the contact paper. Tape the pattern and then the contact paper down on your work surface so they do not slip. Then the colored pattern will help with tile placement.
If you have opaque contact paper, you could to a 'double indirect' method, a version of your idea. See: http://en.wikipedia.org/wiki/Mosaic#Double_indirect_method It is trickier and if you have a lot of open space in your design it can cause more trouble than it solves as the two pieces will want to stick together. Hope that helps! Linda

Corey said...

The cement keeps covering my pattern. Any suggestions or ideas why?

Linda Pieroth Smith said...

I've had this happen occasionally too.
One key is to be sure your contact paper is very sticky- old rolls will sometimes loose their tack a bit. I've had very good results with the clear Contact-brand paper (not the low tack shelf paper). Try to keep the paper clean as you work too from dust and tiny shards from cutting glass or ceramic.

Smooth pieces for your design will adhere best to your contact paper. Some glass, for example, has a bit of texture and will not bond fully with the paper, allowing concrete to seep between the glass and contact paper. I have had some luck using rubber cement as an additional adhesive for those types of pieces.

One other thought- I have noticed that if I let the design sit on the paper for a few hours or overnight that the pieces seem to adhere more fully.
Hope that helps, Linda

Corey said...

Linda,
Thank you!

czechsmix8 said...

I was wondering if you had any suggestions for using small river type rocks for your design. Obviously they don't have completely flat sides to them and therefore the cement seeps under them too much and covers the design. I would like to be able to use the contact paper or something similar so that I can pour multiple stones at a time. I thought about using some type of water based glue that would prevent the cement from covering the design but would then clean up with water. Any thoughts or suggestions?? Thank you!

Linda Pieroth Smith said...

If you plan on covering your stone completely with a design in river rock, one way to achieve this using an indirect method (where you lay the design in the mold and por concrete on top) is to first layer about 1/4 inch of fine sand in the bottom of the mold. Press the rocks into the sand when creating your design. After the stone is poured and unmolded, use a stiff brush to remove the sand.
When the design does not completely cover the surface, I have seen the stones created using a direct method. Pour the concrete into the mold and then add your design on top. I don't feel this way is as enduring but if the stone will be purely decorative, this method may work fine.
To do this sort of design with the indirect method is more challenging. I think you'd need a glue that would stay just under each rock. All the water based glues I am familiar with would flow too much. If the rocks are fairly flat, rubber cement (contact cement) may work. Another thought- perhaps some sort of play doh type clay?? Also try hot glue and see if it would peel off the rocks but stay long enough to create the stone.
Linda