Wool Dryer Balls

lburkey21

Has anyone made their own?? I attempted to but am having an issue getting them to felt. I bought 100% wool yarn and made 4 balls. I have them all tied off in a stocking and have washed/dried on HOT about 3 times. They still don't look like they've felted at all. Am I missing something? Do I just need to keep washing and drying? I was all proud of myself for making them but am really frustrated and ready to just buy some off Amazon instead.