i installed it a week ago today and i have these thin little lines under the tip of the tip and they werent there before i mean there only like a 1/4 an inch long and about 1 centemeter in width but dose any one know what this could be from? is it from heat because it is right on a weld line and one is right next to this , everything still works fine and it would take a perfectionest like myself to notice it, so if this has happened to anyone else i would really like to know why and what i am doing wrong?