I have heard of people putting their HS in the toaster oven at a low temp until the thermal material liquifies and then just wiping it off, followed by a cleaning with rubbing alcohol. I have never tried it and don't necessarily recommend this, but I figured I'd pass the info along. Alot of people also just scrape it off with a razor blade, but be careful with this--you don't want to scratch the HS! Good luck.