Introduction
The crutch foot is the contact point between the escapement’s crutch and the pendulum leader. Its shape and fit determine how impulse transfers to the pendulum, how stable the beat is, and whether the clock runs reliably. Choosing the wrong crutch foot leads to fluttering, uneven beat, poor amplitude, or complete stoppage. This guide explains how to choose the correct crutch foot for your mechanical clock.
Understanding What the Crutch Foot Does
Transfers impulse to the pendulum
The crutch foot pushes the leader, keeping the pendulum swinging.
Controls beat stability
A properly fitted foot ensures even tick‑tock spacing.
Maintains pendulum alignment
The foot must match the leader’s geometry to avoid drag or binding.
Types of Crutch Feet
Flat crutch feet
Common in modern movements; provide broad contact with the leader.
Forked crutch feet
Used in clocks where the leader passes through a slotted fork.
Curved or bent crutch feet
Found in antique clocks; shaped to match specific leader profiles.
How to Identify the Correct Crutch Foot
Match the leader style
The foot must align with the leader’s impulse surface—flat, slotted, or forked.
Check the foot width
Too wide causes drag; too narrow causes unstable impulse transfer.
Verify the crutch rod diameter
Feet attach differently depending on the crutch rod’s thickness and shape.
Matching Crutch Feet to the Movement
Identify the movement manufacturer
Hermle, Urgos, and Kieninger use specific crutch foot shapes and widths.
Match the escapement type
Recoil and deadbeat escapements require different impulse geometries.
Check beat adjustment compatibility
Some crutch feet are designed for auto‑beat systems; others require manual adjustment.
Common Crutch Foot Materials
Steel crutch feet
Durable and ideal for precise impulse transfer.
Brass crutch feet
Common in antique clocks and lighter pendulum systems.
Alloy crutch feet
Used in modern movements for reduced friction and improved wear resistance.
Common Mistakes When Choosing Crutch Feet
Incorrect foot width
Causes drag, fluttering, or unstable beat.
Wrong leader compatibility
The foot must match the leader’s shape and impulse surface.
Improper crutch rod fit
Loose or tight attachment leads to poor impulse transfer.
Recommended Internal Links
- How to Choose the Correct Clock Crutch Assemblies
- How to Choose the Right Clock Beat Adjustment Mechanisms
- How to Choose the Right Clock Pendulum Leaders
- How to Choose the Correct Clock Suspension Posts
FAQs
How do I know which crutch foot my clock needs?
Match the foot width, shape, and leader compatibility to the original movement.
Why is my clock fluttering or double‑ticking?
The crutch foot may be too wide, too narrow, or misaligned with the leader.
Can I bend a crutch foot to adjust it?
Minor adjustments are possible, but over‑bending weakens the metal.
Do crutch feet from different brands interchange?
Only if the width, shape, and crutch rod attachment match exactly.
Why does my clock stop after a few minutes?
Poor impulse transfer from an incorrect crutch foot is a common cause.
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