As far as checking the tension on your rollers what I do is I put a piece of wood down and aim the torch at it and pull the trigger … if there is enough tension the wire won’t stop it will bend … then on the other hand you don’t want the tension do tight that it cuts little groves in the wire because it’s pinching too hard. On the point of fouling the tip … I sometimes get some of that so I periodically spray a little non-stick on it.