How to reduce Physical Material Friction to a negative value UE 4.13

Hey guys,
Just as the title states i’m trying to create a sliding on ice effect for a game and once the character steps on this part of the floor, they should begin to slide. I found a method online which has to do with using a physical material and reducing the friction to a negative number (-1000) and assigning it to a mesh and then assigning that mesh to an object. My issue is that I am unable to go lower than 0.0 for the friction setting for the physical material. I am running version 4.13.2. Any help would be greatly appreciated. Thanks.

In your physical material enable override Friction Combine Mode. Then next to the Friction combine mode from the drop down choose either min or multiply. This will allow you to get smooth ice sliding behaviour. It basically checks your current physical material against the surface it interacts with. For instance setting it on multiply and using a friction value of 0 will make it slide for pretty much eternity. (which is a long time btw) Choose any low value under 0.2 and you’ll get sliding value’s that diminish.