Saw this on t.v.very interesting and time consuming I would think.

The rubber ball is just an armature for concrete sculpture and not the actual substrate.

ahhhhhhh...now see, if I had READ the article...DOH!

Also, the ball will eventually deflate - even just a little.

The thinset and mesh provide a much sturdier substrate than a rubber ball alone.

Thanks for the link. I've saved several of my sons basketballs, smaller and regular size. Eventually, I am going to look at the expert advice here and hypertufa forum and now this article to get going on them. Still don't know if they will be spheres or itty bitty planters. I'm thinking they might be good to package up packets of seeds or small plants for Easter or Mother's Day. Ask me closer to the time how much progress I've made......

So if the ball deflates in the future, will it crack the thinset you think?
Bianchi

no. the thinset is not the substrate. An acrylic concrete with fiberglass mesh is the substrate - at that point the ball becomes inconsequential and was considered a temporary form in which to make the concrete sphere. The thinset is applied to that.

If it were applied to the rubber ball it surely would crack as the temps change the inflation rate of the ball.
I have read that can be a very big problem with applieing concrete on an inflated ball if temps change IE working outdoors.

That sounds WAYYYYYYYYYY too complicated...I'll stick to bowling balls LOL!