> > >Other thoughts:
> > >Concrete containing expanded polystyrene (styrofoam) is already 
> > >fairly common.
> > >Maybe you could just add some baking soda to your concrete? ;-)
> > 
> > Well, I was thinking of ping pong balls ...
> 
> Or just lay perforated plastic pipes at the bottom, and pump 
> air in so that it bubbles up into the setting concrete - it 
> works with Aero chocolate!  :-)
> 
> Cheers,
> 
> Howard Winter


I went to the Aero bar factory once.  Apparently they use a vacuum to get
the bubbles.  Same technique as getting air out of silicon molds, put it in
a vacuum, bubbles expand and pop.  Except with silicon you try not to get
too many bubbles in the mix in the first place.

Apparently the trick with Aero bars is getting the vacuum just right...
"Aero Bar" - now with 50% British air!

Tony

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