I recently got the ultimate bargain on eBay: someone who was doing a house clearance sold 6 pairs of old brass doorknobs. I bought them for £30. Pretty great considering you can normally expect to pay about £20 for a pair. The only slight problem was they were old, stained and had paint on them. Luckily, I found an easy way of cleaning them up to make them look shiny and new again. Read on to find out how easy it is to clean dirty brass using things you probably already have at home.