I have some painting to do on an old house. The paint has chipped away from overall about 25% of the surface, so parts of the siding have grayed a bit from exposure. I plan to scrape all loose material then go over exposed wood with a sander to get rid of the weather damaged top layer. What is a good way to get the chips and most of the old paint off? I have read about tools that heat up sections of the clapboard and loosen the paint that way, but they are very expensive. I also have a friend who has used a propane torch, but it seemed like an accident waiting to happen. I was thinking something along the lines of a wire wheel on a right angle grinder... is that reasonable? thanks!