304 stainless flame tamers

I am trying to build new flame tamers (grease shields) for my grill.  The old ones rusted, which makes sense because they are thin steel and heated up to 800 degrees over and over again.

The new ones will be built with 12x12" 304 stainless steel.  304 stainless can be heated up to 1500 deg F without corrosion.

I bought a cutoff wheel for the chop saw and used that to cut across the 12" of stainless.

RESULTS:
So far the shields are flat and unmachined.  THey are original dimenisons, but not folded or grooved.
The heat in the grill is definitely wrong now-- above the heat shields it is cool and to the sides it is very hot.

I will try to rectify this either by making the shields thinner or adding slots.