diff --git a/src/boardDomain.test.ts b/src/boardDomain.test.ts
index 411be41..e3cd2f9 100644
--- a/src/boardDomain.test.ts
+++ b/src/boardDomain.test.ts
@@ -55,6 +55,7 @@ describe('red thread geometry', () => {
   it('draws a short foreground thread segment into the eyelet from the visual left', () => {
     const leftToRight = threadTagLeadIn({ x: 0, y: 0 }, { x: 200, y: 0 }, 100, 50)
     expect(leftToRight.start.x).toBeLessThan(leftToRight.end.x)
+    expect(leftToRight.end.x - leftToRight.start.x).toBeCloseTo(54)
     expect(leftToRight.end).toEqual({ x: 100, y: 0 })
     expect(leftToRight.path).toMatch(/^M .* C .* 100 0$/)
 
diff --git a/src/boardDomain.ts b/src/boardDomain.ts
index 88e0b22..233834a 100644
--- a/src/boardDomain.ts
+++ b/src/boardDomain.ts
@@ -99,7 +99,7 @@ export function threadTagLeadIn(from: BoardPoint, to: BoardPoint, tightness = 65
   const tagT = position / 100
   const tangent = cubicTangent(from, c1, c2, to, tagT)
   const speed = Math.max(1, Math.hypot(tangent.x, tangent.y))
-  const leadLength = Math.max(.035, Math.min(.18, 42 / speed))
+  const leadLength = Math.max(.0525, Math.min(.27, 63 / speed))
   const entryT = Math.max(0, Math.min(1, tagT + (tangent.x < 0 ? leadLength : -leadLength)))
   const [start, leadC1, leadC2] = cubicSegment([from, c1, c2, to], entryT, tagT)
   const end = cubicPoint(from, c1, c2, to, tagT)