I'm using chicken wings to make a stock, but they want to float up to the top above the water line. Any kitchen hacks to keep them submerged??
I never worry about this. As your stock simmers, the joints, muscle and connective tissue break down and eventually they'll sink in. Sometimes adding a bit of vinegar to your stock first helps with this. Until then, just stir the stock and move the bones around occasionally.
Also make sure that you are keeping the temperature at a very gentle simmer. If you cook at too high of a temperature (at a rolling boil, for example) that will push the meat and bones upwards.
If you have a steamer basket, or a colander that fits in your pot, you can place that upside-down on top and place a weight on it to hold everything down.
I use a drop lid, in a lot of Japanese cooking, the use of a wooden lid which is a smaller diameter than the cooking pot is used to keep foods submerged. But a plate works just a well, it's just hard to fish out of the hot liquid sometimes.