For a very quick stair, all you need is a tread and a riser.
You can just multiply/distribute-1, with virtcal displacemet (equal to total rise) and your treads and risers are modeld perfectly.
Attached is apoor example but I think you can get my meaning from it.
Same for balusters. You just make one set and you can multiply/distribute-1 with virtical displacement and your done.
Now you can spend the time modeling you very fancy hand rails with perfectly modeled newls.
Modeling stairs is great fun. Especially with all of the CAD details and drawings you can get online these days.
Just download their drawings and turn them into 3d parts. It's fun.
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