Thanks guys. I did have a piece of screen in front of my entrance across the hive, stapled at the top to the brood box, and at the bottom to the landing board. Entrance reduced to about 3 inches, and the robbers still made a feast.
This morning a found a few dead bees under the hive and a frenzy in front. Robbing still going on so now I placed a a towel on the hive and see how it goes. I can smell honey around this hive, I think they did a fair bit of damage already.