How to Fix Small Drywall Cracks To fix a hairline crack in drywall, you don’t need a lot of time, effort, or money. Here’s how to do it step by step: Prepare the Surface: Clean the crack by wiping it ...

There are plenty of instances where perfectly good—and often rare—cast iron cylinder head and engine block castings are scrapped due to the presence of a hairline crack in an external surface. Often ...