Check Fit of New Joist

What happens here

Take a piece of the lumber that will be installed into the dado (e.g., a new joist or blocking) and test its fit within the newly cut and cleaned dado. It should fit snugly without excessive force or looseness. Make any minor adjustments with the oscillating multi-tool if the fit is too tight. A perfect fit ensures maximum structural integrity.

Goal: Verify the new joist fits perfectly into the dado