diff --git a/src/main.rs b/src/main.rs
index 3051836..8885614 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -55,6 +55,8 @@ fn main() {
 
 		let n_rack_teeth = 10;
 
+		let r_crown = 18.0;
+
 		let n_teeth = 36;
 		let n_teeth_sample = n_teeth;
 		let r_pitch = 0.5 * n_teeth as f32;
@@ -95,7 +97,11 @@ fn main() {
 				let gear_offset = t * TPS - (n_teeth_sample as f32 + 5.0);
 				let rack_offset = (t * TPS).fract_gl();
 
-				let rack_y_at_x = |x, profile| rack_shape(x - rack_offset * PI, profile);
+				let rack_y_at_x = |x, profile| {
+					let angle = f32::atan2(x, r_crown);
+					let vx = angle * r_crown;
+					rack_shape(vx - rack_offset * PI, profile)
+				};
 				let cutter_y_at_x = |x| rack_y_at_x(x, &cutter_profile);
 
 				let kr_to_xy = |k, r: f32| {