A precision watch case knife designed to open snap-on case-backs quickly and safely. Compact, lightweight and easy to handle, it belongs in every watchmaker's toolkit alongside spare gaskets and silicone grease.
Product overview
This case knife measures 1 cm wide and 11.5 cm long, with a metal tip and a plastic handle. At only 16 grams it offers a balanced grip, allowing the watchmaker to apply controlled pressure without fatigue. With a little practice, a snap-on case-back can be opened in under a minute, providing access to the movement, the battery and most importantly the case-back gasket. It is the most economical and accessible solution for anyone wishing to service a watch at home.
Technical specifications
- Total length: 11.5 cm
- Blade width: 1 cm
- Weight: 16 g
- Tip material: hardened metal
- Handle material: durable plastic
- Compatibility: snap-on case-backs of mechanical, automatic and quartz watches
- Application: case opening for battery change, gasket replacement or movement inspection
When to use it
The case knife is the right tool when your watch has a snap-on case-back, recognisable by a small notch on the side of the case. Use it for battery replacement, gasket renewal or any inspection of the movement. It is not suitable for screw-down backs, which require a dedicated case wrench. The knife is also handy in horology classes and as a backup tool in any travel kit.
How to use it
- Place the watch on a soft mat or hold it firmly in your hand.
- Locate the notch on the side of the case-back.
- Insert the blade carefully into the notch.
- Apply gradual upward pressure with your thumb to lift the back.
- Do not pry too aggressively, you could damage the case-back gasket.
- Once open, work carefully around the movement to avoid disturbing the calibre.
- Wear gloves to protect both your fingers and the watch finish.
Quality and origin
Each tool is shipped from our French workshop and batch checked for blade strength and handle finish. It complements our full range of watchmaking accessories, including silicone grease, gasket assortments and case wrenches.
FAQ
Will it open a screw-down case-back?
No. Screw-down backs require a case wrench or Jaxa-type tool. The knife is reserved for snap-on backs.
Can it damage the gasket?
If used carelessly, yes. Always lift gently and replace the gasket after each opening regardless.
Is it suitable for beginners?
Absolutely. It is one of the most beginner-friendly watchmaking tools, provided you take the time to identify the notch and work slowly.
Recommended companion tools
To carry out a full service we recommend pairing this opener with a set of replacement gaskets, a tube of silicone watch grease and a case-back press. A pegwood stick and a microfibre cloth complete a minimum starter kit. Investing in a watchmaker's vice will further protect both your hands and the case finish, while a digital caliper makes it easy to measure the outgoing gasket before ordering a fresh O-ring.
Safety advice
Always work on a clean, well-lit bench and never apply pressure towards your own body. If the blade slips, redirecting that force toward your free hand can cause injury. Wear cut-resistant gloves when handling tight case-backs, secure the watch in a holder rather than holding it loosely, and keep loose components and small screws in a parts tray to avoid losing anything to the workshop floor.
