Exploding Hollow Concrete Spheres!!

How Temperature Caused a Hollow Sphere Project to Literally Blow Up!

I received an email from Sue, who wanted to share with me this rather interesting bit of info:

You are my hero! I’ve been after the instructions on duplicating Little & Lewis spheres for a year!

I did some on my own and they exploded on my driveway (cold ball from house, 90 degree day= mess.) I just had to tell you about this recent disaster – maybe others can learn from this.


My reply:

Hi Sue:
Well, gee  🙂 Thank you for the compliment. That was very kind of you to take the time to say thanks!

Ummm … the only thing I am confused about is that you say you’ve been “after instructions” for a year to make hollow concrete spheres?? Did you search on the internet?? Because my hollow sphere articles have been available much longer than that. Maybe you mean you were thinking about it, because you just sent me into a panic that my Google rankings had dropped. But no, they are still at the very top! My rankings are:

how to make hollow concrete spheres — #1 and #2
how to make hollow concrete spheres — #1 and #2
how to make hypertufa hollow spheres — #1 and #2
concrete hollow spheres — #1 and #2
concrete spheres — #1
hypertufa spheres — #1 and #2

So you see, my instructional hollow sphere how-to pages are sitting up there at #1, waiting to be easily found.

Anyway … please know my information and how-tos should point you in the proper direction. And I am glad you found my site.

Wow, exploding concrete spheres!!  😯 Now that’s a new one on me! If you had the video of the actual explosion, I’d be begging you to let me put it on my website so we could all learn from it, and maybe get a laugh, too?? (I’m not laughing at your mishap … just the mental vision of the sphere blowing up! ha ha)

But this incident goes to prove that temperatures CAN have a huge influence on the outcome of projects that use inflatable forms and Portland cement – both in the curing and otherwise, as your explosion proved! And this also proves that when making a hollow sphere the temperature of the air INSIDE the inflatable ball needs to be the same as the temperature in the area where you’ll be curing it.

Thanks again for sharing your concrete hollow sphere escapade!


  1. Asphalt says:


    […]Hollow Concrete Sphere Explodes | Tips For A Hollow Sphere Project | The-Artistic-Garden's Blog[…]…

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