Here's a two-page thread on that very subject (WITH Weber's official stance on the subject)!DaveF said:As for the grates: I saw that triangle shape at the store. I think you want flat side up. But I'll have to play with it this summer.
And if you can't wait to find out...
Thanks for choosing Weber. The side you cook on/put food on is the flat side. The grates have a porcelain coating so no seasoning of any kind is required. To clean the cooking grates you'll want to do a burn off after each grill use. After you've taken off the food turn the control knobs to high, close the lid let it burn for 10-12 minutes, turn it off, let it cool and then come back and scrape them clean with your brass or stainless steel bristle grill brush.