BTW a wire wheel would probably clean the old seasoning off faster than a sanding disk. That being said, the sanding disk has the added benefit of giving you a smoother finish on your cast iron, which is nice because most cast iron cookware available in the US is no longer machined on the interior surface. They leave it rough after the sand-forging process.
Gotta be careful with the wire wheel, it's possible to get the surface too smooth and the seasoning won't stick as well. Source: I've stripped and re-seasoned 20+ pans and the one I wire wheeled has never been quite right. People on /r/castiron also advise against it. Even for pans where the sand cast finish was milled smooth from the factory.
I recommend never using any kind of wire wheel, brush or scraper around any kind of food utensils whatsoever. The wire will break and you could ingest a fragment or it could embed in your eye/skin with serious consequences:
The article suggests alternatives such as coil brushes or crumpled aluminum foil instead. Also there are chemical methods.
Wire tools deserve considerable respect and should be used only with protective gloves and eyeware and even skin protection, since spun-off pieces of wire can embed in eyes or bare skin (and you may not notice). Good news: any embedded wire or steel fragment shows up like a lighthouse in an x-ray, making them extremely easy to locate.
So the wire wheel causes this, but not a sanding disc? I trust your experience, but that's very counterintuitive. I've never used either on my cast iron, so I appreciate your feedback.
The lowest effort approach I’ve found to stripping bad seasoning off a pan is to just throw it in the oven on self-clean. But make sure you’ve got the windows open! The results are beautiful but also accompanied by some acrid smoke.
