Baluster (Handrail) Radius
Helix Calculator
Vector Formula for Radius of Curvature
3D Sketch, Plan View and Development
h = Height required for Helix to complete           one revolution about the Cylinder
c = Circumference of Cylinder
r = Radius of Cylinder
C = Circumference of Baluster Circle
R = Radius of Baluster Circle

Solution of Baluster Radius
If the Helix does not make a complete revolution the formula still returns the same Baluster Radius. For a quarter of a revolution through 90°:
90° ÷ 360° = 1/4
The term 2π in the Helix Run is replaced by 2π ÷ 4 = π/2
The Helix Rise = h/4
The Cylinder Radius r remains the same.

Solution of Baluster Radius for 90 degree turn
Joe Bartok