Fake Stones





Introduction: Fake Stones

Give your garden an extra touch with these light and fake stones made from foam and clay. It's also a fun project to do with children.

The stones are made from a material I call "sandy foam". A combination of expanding foam and sand. More explanation about the material I used for this stones, experiments with it and all the possibilities, look at my previous Instructables: Flexible And Light Stone Material.

Step 1: Clay Stone Shapes

As basis shape I clayed stone shapes with "Model Magic" from Crayola. Make little balls by rolling clay in your hands, then press to create a stone shape.

Step 2: Mix Ingredients

For the sandy foam I used flexible polyurethane foam of Douglas & Sturgess. I used 0.10 oz of part A, 0.30 oz of Part B and 1.30 oz of sand. Mix it for at least 30 seconds, and add little amounts of sands in between.

Step 3: Prepare Working Area

Cover your work area with sand so you can lay down the stones to dry without them sticking to the surface.

Step 4: Model Sandy Foam Around Shapes

Get some of the sandy foam in your hands and model it around the clay shape. It will be sticky, so wear gloves and in between you can sprinkle sand on your hands so the foam doesn't stick to your hands. It will also create a more sandy structure.

Step 5: Let Shapes Dry

Lay the stones down on the sandy surface. You can cover them with another layer of sand, to create a rougher structure.

Step 6: Decorate!

These stones match perfect with the flexible stone pots I made from the same material. Here's a direct link how to make the pots: Flexible Stone Pots.



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    Shape the stone around a plastic container, old film can or prescription bottle and use it to hid a house key or whatever you need to leave for someone that is hidden! Maybe just a deep hole inside the rock (on the bottom of course) and glue a small rare earth magnet inside to hold the key in place?

    To ysabet: I'm a geocacher, too. I'm forever bringing home interesting-shaped rocks and making caches from them. One cacher just published a "spoiler" photo on my page for Noah's Ark, GC27N7P. It's not the best picture of my use of rocks but it gets the idea started. I picked up another great one today just inches from the GZ for a cache that I found. Since each natural rock is unique, they're perfect for the game. Cache on!

    These look great. Do you have an idea on the cost of materials vs. buying rocks?

    1 reply

    as another user said....with this, you can make things that you can't make with regular stone. If you just want rocks though, find a landscaping outfit or go to the river.

    you might want to shellac it or something to help keep the sand on and keep anything funky from the foam from leaching into the water.

    that's a good point. You have no idea what's gonna leach into the water from the foam or how the fish will react to it. It's best to seal it and eliminate the problem altogether.

    just don't use sand with salt on a fresh water aquarium

    NICE! I geocache, and this method would make some excellent cache hides; I'll definitely have to try it!

    Step one . Go outside and find rocks . Step two .........................

    1 reply

    Mt first thought too, but the image with the pots changed my mind. there are a lot of cool things you can do with this that would be hard to do with a real rock.

    JOEKE: Thanks so much for sharing this method. Just 2 questions: 1) Do you let the paper clay forms dry completely before applying the sandy foam? and 2) Do you think this would work for miniature stone walls, houses and the like for scale miniature scenes? I need stones in sizes from .25 inch right up to 1.5 inch diameter. Using aggregate and river stones with mortar makes the finished project very heavy, but I've tried paper clay, carved builder's foam, paper pulp take-out containers, egg cartons and stone wall moulds without truly satisfactory results. Thanks again. :-)

    These look great! I've been thinking of using a similar technique for building fake rock hides for my lizards.

    I see some good pranks coming up by throwing these at friends and family...

    Neat idea