For a well-controlled Charpy program, the most reliable approach is to use a dedicated specimen notching and broaching machine to cut consistent V and U notches, then confirm the notch geometry on an optical notch verification system before testing. This combination reduces operator-to-operator variation and helps keep your impact results tied to the notch requirements of your Charpy method.

In practice, labs typically standardize on tools like these:

• A motorized Charpy/Izod notching and broaching machine with the correct broaching knives for your required notch type.
• A notch verification projector or optical comparator system that lets you align the specimen and compare the projected notch profile to certified reference templates.
• Spare notching and broaching knives so you can maintain consistency after knife changes and routine wear.

A good habit is to verify notch profile at setup, after any knife replacement, and whenever you see unexpected shifts in absorbed energy or fracture appearance.

If you want to confirm the right notch-making and verification setup for your specimen geometry and Charpy method, learn more, learn more, or request a quote.