If the head of a chisel or punch becomes mushroomed, what should be done?

When the head of a chisel or punch becomes mushroomed, the best course of action is to discard it. The mushrooming indicates that the tool has been subjected to excessive impact or wear, which compromises its integrity and effectiveness. A mushroomed head can lead to decreased precision during use, as it will not provide the clean cuts or strikes that a properly shaped tool would.

Using a severely mushroomed tool can pose safety hazards, as it may lead to unexpected failure or injury during operation. Therefore, rather than attempting to reshape or file down a compromised tool, which may not restore its original effectiveness, it is safer and more effective to replace the tool entirely. This ensures that you maintain the quality and safety of your work.