Formula and input notes
Clear gap = [opening − (member count × member width)] ÷ (member count − 1)
| Input | Practical note |
|---|---|
| Maximum clear gap | This is the Spindle Spacing Calculator layout value for maximum clear gap; confirm whether the drawing specifies clear or on-center spacing. |
Worked spindle spacing example
Spindle Spacing Calculator example: Across a 78.75-in opening, the trial pitch is 1.5 in + 4 in = 5.5 in, requiring 16 members. Equal distribution leaves 3.65 in clear and 5.15 in on center.
Use the count as a baseline
Transfer the resulting on-center spacing from a consistent edge or centerline and verify the final clear gaps physically.
Posts, gates, and field conditions
End conditions, decorative turning width, stair angle, newel offsets, measurement tolerance, and local sphere rules influence layout.
Questions specific to this calculation
How does spindle spacing keep the clear gap within the limit?
Enter one clear opening, spindle width, and the maximum clear space. The algorithm increases member count until an equal gap fits the limit.