I have had very good luck recently printing 618 at 245 onto unheated glass bed pretreated with a children's Elmer's Glue Stick - just a thin coat. I've got the kind that goes on purple and dry's clear. "normal" spacing from hot end to glass (as in I'm using the same procedure to level the print bed I use with PLA.) My glass is just double strength glass from the local hardware store - nothing special. Cheap and easy to get and cut.

Much better then my previous method which was again at 245 onto canvas glued to glass (again unheated.)