Rekeying Locks

What Is Lock Rekeying?

Rekeying a Lock Cylinder
Rekeying Lock Cylinders

One of the most common questions our residential locksmiths get asked is, “Can you change my house locks?”

And, yes; we can. But new hardware is expensive and isn’t usually not necessary.

More often what the customer wants instead of a house lock change is what we in the locksmith industry call a rekey.

Lock rekeying is the process of replacing the pins within a lock so that the existing lock no longer works with an old key. The lock will now open using a new, different key. Rekeying locks allows you to keep your existing hardware, while providing the necessary security to ensure no one else has the key to the property.

Lock rekeying is less expensive than replacing the lock. This drastically reduces the cost of protecting your home or business from having access gained by previous owners or tenants.

Parts of a Lock

To understand how rekeying works, you need to have a little knowledge of how a lock cylinder is put together. Although every lock is a bit different, most common home and business locks have the same basic parts. There is the housing, which is what surrounds the plug. The plug makes a tight fit into the housing, and is held in place with some form of clip or cam that keeps it from being pulled out. Pictured here is a key-in-knob cylinder.

The lock housing and the plug both contain holes. These holes accommodate “bottom pins.” Those are the pins that come in contact with your key. When a working key is inserted into the lock, the top part of the bottom pins will be flush with the plug, as shown.

Pins Are Flush After Working Key is Inserted

When the bottom pins are flush, the plug will spin along the sheer line, and that is how the correct key opens the door.

When the key is not in the keyhole, those bottom pins are pushed down into the plug cylinder. They are replaced by the top pins, and the top pins are pushed into the bottom pins by springs.

These pins block the sheer line and prevent the plug from spinning freely.

These 3 items (bottom pins, top pins, and springs) are secured either internally or with a spring cap, to keep everything held together.

This Key Will Not Open the Lock Because the Plug Cannot Spin at the Sheer Line

When a key with cuts that match bottom pins in a cylinder is inserted, they create a shear line; a level surface at the edges of the plug that will allow the plug to turn freely.

In fact, using multiple stacks of pins, you can actually create a cylinder that has multiple shear lines. That is, more than one cut key will create a shear line, so more than one key will open the lock.

This is called ‘master keying’ and is used in businesses extensively. One person might have a key to access many office doors, but another will only have a key to open his/her office door.

Check out our article “What is Master Keying?”

Rekeying Lock to Match Existing Keys

Many times the need to rekey a lock occurs when a new lock is purchased and you want that new lock to match an existing house key.

This is no problem, so long as you buy a lock that is the same keyway as your existing locks. See our article on Rekeying Locks to Match Existing House Keys.

How to Rekey Locks

Taking your own locks into a lock shop is one of the most affordable ways to rekey your own locks. See our article, “How Much Does it Cost to Rekey Locks?” But if you’re the type that wants to figure it out and pay the absolute minimum, then rekeying your own locks may be for you.

You can rekey your own locks by removing the lock from the door, taking out the cylinder and then replacing the bottom pins. As a practical matter, it may not be worth it. A single mistake can make the springs and pins fly out, all over the place, and a locksmith (or replacing the lock) will certainly be needed to get it all back together.

DIY Schlage Rekey Kit from Amazon

I’ve often had folks who’ve tried to go it alone come into one of my shops when something went wrong.

If you are willing to take on the challenge, you can buy rekey kits on Amazon. If you are handy, it could be fun to try to rekey the lock yourself. If it works, great! If not, just take the locks into a local locksmith shop and they’ll get it back together for you.

How to Rekey Kwikset Locks

There is a lock manufacturer, Kwikset, that around 10 or 12 years ago designed locks for residential use that you to quickly and easily rekey your own locks. The product line is called SmartKey, and it’s a very different lock system that does not use pins and springs.

kwikset smartkey lock

You can identify a Kwikset SmartKey lock by the extra little hole found near the keyhole.

ACME Locksmith sells rekey kits for Kwikset locks on our website at a very affordable price. It comes with everything you need in order to rekey your own Kwikset locks including the smart key reset tool and new keys. You can specify how many keys you’d like to have with the kit.

Rekeying a Kwikset Smart Key DOES require the existing working key, so if you do not have this, you cannot rekey the lock. A locksmith would be able to, though, using a special tool needed to reset the lock with a working key. If you do have the working key, it’s a fairly simple process.

  • To rekey a Kwikset lock, insert the existing key into the lock and turn it 90 degrees in the direction to unlock the door.
  • Insert the smart key reset tool into the slot until you hear a click then remove it
  • Remove the existing key by pulling it straight our (do not rotate it back)
  • Insert the new key into the keyhole and now rotate the key back to the original position and remove the key
  • Check your old key to make sure it no longer works

Video Demo – How to Rekey a Kwikset Lock

Demo: How to Rekey a Kwikset Smartkey Lock

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