Russ installs a 20 W head and repeats the basic diagnostic work rather than assuming it behaves like the 5 W and 10 W units. He checks practical focus, beam shape and the ability to produce high-intensity marks on harder materials.
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What You’ll Learn
- Why each new diode head needs its own beam and focus tests.
- How focus can appear different on soft and hard materials.
- Why spot-shape claims should be checked on the actual workpiece.

Start Again with the New Head
The 20 W module has different optics, airflow and mechanical construction. Russ therefore re-establishes the working focus and observes the burn rather than carrying settings over from previous heads.
Marking Harder Materials
Tests on slate, anodised aluminium and metal-related surfaces reveal whether the increased power also delivers the required intensity. More nominal watts do not automatically produce a cleaner or more useful spot.
Why This Session Matters
It shows the value of re-characterising every head rather than assuming a simple power scale-up.
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