If you want a bunch of mini-graphs combined into one graph, try the Wrap option.
dt = open("$sample_data\Bands Data.jmp");
gb = dt << Graph Builder(
Size( 1832, 943 ),
Show Control Panel( 0 ),
Variables( X( :timestamp ), Y( :viscosity ), Wrap( :customer ) ),
Elements( Bar( X, Y, Legend( 7 ) ) )
);