Case Opener

Specification

Technical parameters

Overview

Case openers fall into three families. A Jaxa-style wrench uses three adjustable pins that engage the notches in a screw-down back and turn it. A knife or lever opener works on friction-fit snap backs, prising at the seam. A pneumatic or press-type opener holds the case and applies controlled pressure, which is the gentlest option for backs that are stuck.

The failure mode is always the same: the tool slips and scores the case, or it applies force to the crystal rather than the back. Adjustable pin wrenches must be tightened so all three pins bear equally before you turn, and the case must be held in a case holder, not in your hand.

Friction backs are the ones that injure people. They release suddenly, and a knife blade that lets go at that moment has nothing behind it. Use the thinnest blade that will enter the seam, work slowly around the circumference, and never prise against the crystal.

What matters about it

• Adjustable pins suit most notched screw-down backs
• Lever blades suit snap-fit friction backs
• Press types apply controlled, even pressure
• Brass blades mark soft cases less
• Case holder should be used with every type

Practical notes

• Tighten the pin wrench until all pins seat fully before applying any turning force.
• Warm a stuck screw-down back slightly before forcing it — the gasket may simply be adhered.
• Open the case with the crystal facing down on a clean pad, never face up.
• If the back will not move, stop and check for hidden screws or a bayonet fitting.

Compatible with