Susan898 is right about old coating being unsafe. But the real kicker is the TOXIC DUST that flies everywhere when you strip it. That garbage ruins your lungs and coats your whole garage. A basic shop vac with a fine filter solves that problem fast. Plus, a lot of that old insulation contains lead, which is a major health risk. Dealing with that correctly can add value since you're handling hazardous material properly. It's not just scraping wire, it's managing a health hazard.