A scratched lug is the most common accident during a strap change. It is always avoidable: the right awl, the right angle and the right sequence are all it takes. Here is the workshop method in 7 steps.
Choosing the awl: Ø 0.80 mm, 18° angle
A positioning awl is NOT a makeshift pin punch: its tip is cylindrical over the last 2 mm and then tapers at 18°. This geometry lets you press into the groove of the spring bar without slipping.
- Ø 0.80 mm: fits the standard grooves of Ø 1.50 to 2.00 mm spring bars.
- 18° angle: gentle, does not slip, does not chew the groove.
- See our positioning awl and our complete repair kit.
Setting up the bench — 2 minutes
- Work surface: green watchmaker's fibre pad (it accumulates scratches, but is gentle). Never on tiles.
- Lighting: gooseneck lamp aimed at 45° on the right-hand side of the lug, so the shadow of the spring bar is visible.
- Case holder or Rodico Bergeon adhesive putty — the watch must not move.
- 5× or 10× loupe on a head loupe clip.
Removing the old spring bar — 4 steps
- Identify the movable-shoulder side of the spring bar: it is the one where the groove is visible at the lug/strap junction (often only one of the two shoulders is retractable).
- Insert the tip of the awl into the groove, holding the awl at 10° to the plane of the strap (almost parallel), never perpendicular.
- Press while sliding the movable shoulder towards the centre of the spring bar — only 0.4 mm of compression.
- Pivot the strap outwards from the case while keeping the compression: the released shoulder comes out of the lug. Let go: the other end falls out on its own.
📍 The correct angle of attack: 10° to the plane, not 90°. At 90° the awl slips across the lug and scratches it.
Fitting the new spring bar — 3 steps
- First insert the fixed end (non-retractable shoulder side) into its lug hole. The spring bar is now held on one side and free on the other.
- Compress the movable shoulder with the awl (always 10° angle, not 90°), sliding the spring bar towards the free lug.
- Release the pressure: the shoulder engages in the hole with an audible little click. Check by gently pulling on the strap: it must not move.
« The click of a spring bar snapping home is the only sound that says "it's seated". If you do not hear it, it is not seated. »
The 5 mistakes that scratch — absolutely to avoid
- Awl held perpendicular to the lug: one slip and the lug is marked for life.
- Awl too big (Ø 1.0 mm in a 0.8 groove): the tip slips out of the groove and marks the metal.
- Kitchen knife or nail scissors: no conical angle, slipping guaranteed, scratch depth 0.1 mm.
- Too much compression (> 0.6 mm): the spring is permanently deformed, the bar no longer holds, back to square one.
- Working without a case holder: the watch turns under pressure, the awl skids across the bezel.
FAQ
What if my spring bar has no visible groove?
It is a slotted pin (Omega, Breitling). In that case a Ø 0.80 or Ø 1.00 mm pin punch is used directly through the lug hole — see our pin punch guide.
Should a new spring bar be degreased before fitting?
No. New spring bars leave the factory with no residual grease. If you have touched the shoulders, a quick wipe with a chamois is enough.
How do I repair a scratched lug?
Light scratch (< 0.02 mm): polishing with Dialux Green compound on a flexible buff. Deep scratch: a trip to a professional polisher, €40 to €80 depending on the watch.
Is there a "consumer-grade" tool with no risk?
Yes, quick-release spring bars (side lever) — no tool needed, you operate them with a fingernail. They are, however, incompatible with thick leather straps and NATOs. See our quick-release spring bar.