Thanks racer1812. I knew I shouldn't sand the tip, but thought I'd try as I couldn't get the tip clean using the method provided in the Hakko instructions. Still trying to figure out the heating issue. I have emailed and called Hakko and have not heard back from them yet. I tried to contact them via their live help online, but can't seem to get that website feature to work. My LHS is out of tips right now, but I'll pick one up when they get them back in stock and start over. I'm a little disappointed in Hakko for not contacting me back yet...been a week.