To build a spare key set without mixing in untested copies, treat each new copy as unproven until it works at its own lock. Keep new copies in a holding spot away from your daily ring, test each one, write down the result, and move only the copies that pass into a separate spare set. The real danger is a bad copy hiding among good ones.
Why a spare set needs two states
A spare key set works better as a process than as a container. Each new copy starts out untested and earns its place among the tested spares. The key itself does not change. What changes is what you know about it.
An untested copy looks exactly like a tested one. Once they share a ring, the only way to find the bad one is at the door, and usually at a moment when you have no other key with you.
What to settle before the copies are made
Before copies are cut, write one line per spare: the lock it is for, why it exists, and who will hold it. For example: front door deadbolt, backup if the daily key goes missing, kept at home. That line gives each copy a job you can check it against later.
Add two notes. Name the source key, the one the copy will be cut from, and pick one that already works smoothly at that lock. Then decide when you can stand at each door and test without someone waiting. That matters most for storefronts and shared entrances.
How do you test a new key copy before relying on it?
Test each new copy at the exact lock on its line, while it is still kept apart from your daily keys. A copy passes only when all of these are true:
- It slides fully into the keyway, the slot in the cylinder, and sits as deep as the original does.
- It turns with about the same effort as the original, without wiggling or pressing it a certain way.
- It turns back and pulls out cleanly.
- It does all of this several times in a row, not just once.
- On a door with a bolt or latch, it works with the door open and again with the door closed.
The open and closed checks tell you different things. With the door open, the bolt moves freely, so you are testing the key against the cylinder. With the door closed, the bolt has to reach into the frame, and any rub there shows up as stiffness in the key. If the original drags the same way, the door or lock is the likelier cause, not the copy.
Doubt counts as a fail. A copy that needs jiggling or works only on the third try goes into an envelope marked failed, with the lock named on it. Do not try to fix it at home. Left as it is, the copy shows what went wrong.
Write down the date, the lock, and the result for each copy, pass or fail, before you leave the door.
Keeping holding, spare, and daily keys apart
Keep three separate places. The holding spot, such as a marked envelope in a drawer, is for copies not yet tested. The spare spot, indoors and away from the door it opens, is for tested copies only. The daily ring is what you carry.
A copy moves from holding to spare after it passes, and onto the daily ring only to replace a lost key, with your notes updated to match. The one rule that holds the system together: a tested spare never shares a ring or a pocket with an untested copy.
Re-check the spare set when a lock is rekeyed, meaning its pins are reset so old keys stop working, or when a spare comes back from a loan.
What to bring back when a copy fails
When a copy fails, bring the source key, the failed copy, and your note on which lock it was tested at and what happened. A copy that would not go in fully points somewhere different from one that went in but would not turn. A failure that showed up only with the door closed may not be a key problem at all.
Upper East Locksmith offers key cutting and duplication, along with lock replacement and rekeying when the lock turns out to be the trouble. To sort out a failed copy or extend the set, call (347) 444-9725 with your notes in hand.
Frequently asked questions
Should a spare key be tested at every lock it is meant to open?
A spare key should be tested at each lock it is meant to open, one lock at a time. Locks set to take the same key can still wear differently, so a copy that turns smoothly in one cylinder can stick in another. Record a separate pass or fail for each lock.
How often should a stored spare be checked again?
A stored spare key is worth trying at its lock on a routine you will actually keep, such as once each season, and again right after any work on that lock. A spare that sits in a drawer does not wear, but the lock it opens does, so a regular try catches a change before an emergency does.
Is it a problem if a new copy works but feels stiffer than the original?
A new key copy that works but feels stiffer than the original should be treated as doubtful. Compare both keys at the same lock. If only the copy feels stiff, set it aside as failed. If both feel stiff, the lock itself is worth having looked at.
Should the tested spare set be kept in one place or split up?
A tested spare set can be split, as long as each spot holds only tested keys and your notes say which spare is where. One spare indoors and another with a person you rely on means one lost set does not take every backup with it. Do not hide spares outside.