Spiral Stair with Center Pole AMS manufactures all components of our spiral stairs in shop. Most spirals are at least 270 degrees with 22.5 deg. or 30 degree treads. Treads are attached to a 12 or 16 sided center pole, using a steel slide lock.
Strength is gained from the front and back tread baluster .
This spiral is made from Yellow Pine, rotates 540 deg. Below is a 360 deg.