Thumb / Butterfly Screw

Thumb / Butterfly Screw

Quick look

  • Adjustment access: Hand-adjustable dial—no tools needed, even mid-service.1
  • Closing feel: Smooth enough for daily work, though not as glassy as bearing systems.1
  • Ideal use case: Shared shears or mobile stylists who need to tweak tension quickly without a key.1,2
  • Care level: Moderate. Keep threads clean so the screw tightens evenly and doesn’t back off.1

Why it matters

Thumb and butterfly screws trade the precision of a flat screw for speed. Their wide, winged dials let you bump tension tighter for thick sections and loosen it for dry glide without leaving the chair. For salons where tools change hands all day, the convenience is hard to beat.

How it works

  • A threaded thumb screw compresses the washer stack. The oversized head gives leverage so you can make small adjustments by hand.1
  • Some modern designs include a mini leaf spring or click plate to add stability, but most rely on friction alone—so frequent checking is key.1,2

Adjustment map

  1. Clean and oil the pivot, then close the blades.1
  2. Turn the butterfly clockwise in small increments until the drop test stops around 35°–45°.1
  3. If you loosen for slide work, remember to tighten again before heavy blunt or over-comb passes.1

Best for

  • Stylists who share shears between stations and need a universal adjuster.1
  • Mobile or on-set artists who may not carry a toolkit.2
  • Training kits that teach tension basics without requiring a screwdriver.1

Watch-outs

  • Threads clog quickly—wipe product and hair away so the screw seats evenly.1
  • Because there’s no ratchet, the dial can drift during long cutting blocks; recheck tension frequently.1
  • Over-tightening with bare hands still compresses the washer stack; stop as soon as resistance increases.1

Maintenance notes

Wipe the screw head after every service, oil lightly, and retighten at the start of each day. During sharpening, ask the technician to clean the threads and verify the washer stack hasn’t warped.1,2

Related systems: Flat Screw • Click Dial / Ratchet

Sources

  1. JP Scissors USA – Tension Adjustment Guide
  2. Saki Shears – Adjustable vs Fixed Tension

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