Posted for "Ron Raby" <ronr@advanceddesign.com>:

 Gary
 
 I used a very high flox micro mix, with flox being most of the material. I
 think your idea of a one bid only on the outside would only make it better.
 Maybe try a sample both ways and whack it with a hammer and see how it holds
 up.
 
 Ron Raby