Bonding stone together with Product #17 – Epoxy Stone Adhesive is attractive and functional. It allows you to have the look of natural rock. This “natural rock” will let water pass through it just like its non-epoxied counterparts. It is however a good choice when you don’t want that stone to be moved, accidentally or on purpose.
This function is so nice that I am seeing projects where larger and larger stone is being utilized for the same reasons (above) as the small stone. There are a few shortcomings that should be avoided when bonding larger stones.
You want to make sure when selecting your stone that it is not too round. Round stone reduces the square inches of surfaces touching each other that are bonded together. That reduces the strength of the material, by reducing the square inches of bonding surface. If angular stone is used (as in the picture above) you increase the surface area touching each other and increase the strength.
If you want larger stones in the mix, I suggest you use a variety of smaller stone to fill in the large gaps between the bigger stone. If you combine a mixed gradation of stone that is also angular (not round) you can get an excellent compromise of strength and large stone beauty.
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