Are you sure your door locks are safe?

Here is a practical self-inspection guide to judging door lock security, based on the on-site experience of experienced hardware mechanics:

● Lock Cylinder Security

▸ Check the Key Shape

High Risk: Flat or cross-shaped key (can be opened instantly with a wire)
Relatively Safer: Rotary key with curved grooves (requires over 15 minutes for skilled lock picking)
Most Reliable: C-grade lock cylinder with double-row serpentine grooves and anti-drill plates (professional thieves avoid this)

▸ Test the Lock Cylinder

When inserting and rotating the key:
Smooth and without jamming → Internal pins are not worn
Need to shake the key → Pins become loose, key → Loose pins, easily pried open with tools

● Lock body's resistance to damage

▸ Check materials and structure

Scratching the lock body with a fingernail: Leaves scratches = inferior alloy; No scratches = 304 stainless steel
Number of bolts: Single bolts are easy to pry; choose at least a three-bolt lock (main bolt + two auxiliary bolts hooking the door frame)
Lock bolt material: Pure copper or steel; magnets do not attract it = high-quality materials

▸ Violent test (self-check)

Push the bolt forcefully with a screwdriver:
Lock bolt retracts → internal spring in the lock body breaks
Door frame shakes → Secures
Door frame shakes → fixing screws are too short (should be ≥5cm)

● Fatal flaws in smart locks

▸ Electronic components

Strong magnet on the panel: If it unlocks automatically: If it unlocks automatically = clutch is forward-mounted (hackers can bypass it through the door)
Covering the fingerprint sensor: If it can still recognize the fingerprint sensor after covering it with transparent tape = no liveness detection
Removing the battery and restarting: Restores factory settings Removing the battery and restarting: Factory reset = no tamper alarm function

▸Mechanical backup

Check the emergency keyhole:
Hidden design (requires removing the cover) = safe
Direct exposure + cross key = most exposed + cross key = weakest link

●Installation hazards

▸Door frame strength

Strike the door frame corresponding to the latch with your fist:
Dent in the wooden board:
Dent in the wooden board → No anti-collision steel plate installed (requires adding a 3mm thick steel plate)
Screws protruding less than 2cm → easily kicked away

▸Latch gap

Insert a bank card when the door is closed:
Can be inserted into the gap → Thieves can use a plastic piece to pry open the lock tongue.
Ideal state: A card inserted ≤3mm should be stuck.

●Maintenance and Upgrades

▸Annual Maintenance Procedures

Inject graphite powder into the lock cylinder (do not use oil-based lubricant).
Tighten all screws.
Tighten all screws (especially those on the door frame side).
Wipe fingerprints and oil stains off the smart lock.

▸Necessary Upgrades

Add top and bottom bars to older locks (insert steel bars at the top/bottom of the door).
Dual unlocking for smart locks - Implement dual authentication for smart locks (e.g., fingerprint + password).

●Immediately Discontinue Signal Use

Replace the lock on the same day if any of the following occur:
** The key can rotate 360 ​​degrees (lock cylinder is unusable).
** Fresh scratches on the keyhole of the door frame (tested by a lock pick).
** The smart lock panel lights up blue for no reason (due to wireless interference).