It's for housed stringers, so it will route out the run with nosing, and the riser. It will also include the space needed for stair shims. No baltic birch necessary, I have made these before but always out of plywood. There is no rise/run, or pitch, it's simply one tread and riser. I clamp it down, route and then move it to the next step and repeat. The rise/run is set by the angle that the template is clamped to. The real question remains, practical advice on routing aluminum.
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