Trade geometry · Circular layout
Lay out an equal bolt circle.
Convert entered diameter, hole count, start angle, and origin into spacing, chord distance, and explicit X/Y centers.
← Bolt circle diameter →↕ Hole diameterCenter point · equally spaced holes
← Start angle from +X axis →↕ Angular spacing← Adjacent-hole chord →Counterclockwise coordinate order
1 Enter circle and hole geometry
2 Set coordinate origin
Transparent calculation
Hole angle = start angle + index × 360° ÷ hole count.
Each center is X = center X + radius × cos(angle), Y = center Y + radius × sin(angle). Adjacent chord is 2 × radius × sin(π ÷ count).