The key to flipping salmon without it falling apart is to make sure it's READY to flip. Try to flip it too soon and you're asking for a nightmare. When you place the salmon fillets on your grill they will naturally stick to the grills during the first few minutes of cooking before starting to release (about 4-5 minutes grilling covered for me)- then it's time to flip. If you feel resistance when trying to flip, stop and give it more grilling time! You also have to make sure to flip it carefully! Use a spatula and slowly slide it under the salmon fillet, wiggling it ever so slightly. Then flip carefully.