Sometimes butter leaks out of my cheesecake base when it's setting in fridge overnight why is this ??

No it's a no bake cheesecake sometimes is leaks sometimes they don't. Not sure if I'm warming butter up too much or not enough etc

Found a great site that may help you... beyondfrosting.com
Their ratio for graham cracker crust is 8 T unsalted melted butter to 2-1/2 C finely crushed (that was important, super fine crumbs) graham crackers. They also line the springform pan with parchment paper. It has a ton of information, I bookmarked it for my own reference. Hope this helps..good luck! BB