Mechanical filament-cut counter

Requirement

Problem

The cutter is a visible repeated mechanical event that could be counted for maintenance and display.

Why now

It is a distinctive add-on that can also become a maintenance indicator if it stays mechanically passive and low-force.

Exact requirement

Design a passive counter actuated by the cutter stroke that increments once per cut without adding electronics.

Compatibility

A1 reference release only until cutter stroke force and envelope are measured on each printer variant.

Release Gate

Counter does not increase cutter force enough to affect reliability and remains resettable/serviceable.

Acceptance criteria

• Increments exactly once per cutter stroke in repeated tests.
• Does not change cutter travel, force, or recovery behavior.
• Can be reset or serviced without disassembling calibration-critical parts.

Launch assets

• Cycle-count proof video.
• Reset/service instructions.
• Clear experimental label until long-run testing exists.

Prototype Plan

Use the cutter stroke as the only input and isolate the counter from the cutter force path with a low-friction one-way ratchet.

Next build steps

• Prototype an external one-way ratchet with very low actuation force.
• Bench test the counter by hand before installing it on a printer.
• Only move to printer testing after the cutter can complete the same stroke without the counter installed and installed.

Measurements needed

• Available cutter-stroke travel that can be observed without loading the cutter.
• Maximum allowed actuation force before cutter reliability changes.
• Mounting envelope outside bed, wipe, PTFE, and slot-bank movement.

Safety Boundaries

• Must not increase cutter force enough to cause missed cuts or toolhead errors.
• Must sit outside the cutter force path and stay clear of the rear slot row.
• Must fail passive: if it jams, the cutter and print workflow still need to remain safe.

Evidence source

Owner requested a mechanical counter that tracks the number of filament cuts.