1. buy 1/2 inch copper piping and get a piece of 3 inch pipe.
2 coil the copper around the 3 inch pipe to get your shape.
3. discard 3 inch pipe and slide the coil down inside a 4 inch pvc pipe 2 feet long 1/2+1/2+3= 4 so it should fit mine did
4. drill hole in the bottom about two inches up so there is still room to slide the end cap on without blocking the hole.
5. use L pipe to make right angle to attach the funnel fill core with ice and water let sit for a couple a minutes and then use.