In this section we will review some of the common mistakes and errors that can happen during a rekey. Mistakes and errors are diagnosed by their symptoms. A single symptom may have several possible causes. Do not be discouraged. As a rule, I like to say that something goes wrong every job. Many mistakes can be avoided by carefully following all the steps; others can be easily corrected once you gain more familiarity in working with locks.
Key does not turn the lock:
If the key does not turn the cylinder this means that your rekey failed. Likely it is because the pins used were not precise enough. To fix this you have to rekey the lock again. Remove the end-cap, c-ring, tailpiece, set pin and set spring. Insert the key and jiggle it around to see if you can find the sheer line and turn the cylinder. If this fails you will need to pick or shim the cylinder. Read chapter 2 to learn how to pick and shim a cylinder. From here you follow the remaining steps required to rekey the cylinder, starting with inserting the follower.
In the future, this problem can be avoided by increasing your expectations for quality of work. Always be sure that the bottom pins are flush in the core. Use your fingers to feel if it is flush. Don’t be afraid to get in close and look. As always, gaining familiarity and experience with rekeying locks will make you better at rekeying.
Key won’t come out:
You just rekeyed the lock and now the keys won’t come out. This is a common symptom. 9 times out of 10 the cause is an end-cap that is loose. To remove the key, apply pressure to the front of the core with your finger and remove the key. To prevent this from happening again, tighten the end-cap until it is snug. Warning: over tightening the end-cap will create other problems.
There are a few other less likely reasons that a key can get stuck in the cylinder. The first is that the top and bottom pins are too large for the chamber. You may notice that the key is difficult to insert into the keyway. This can be fixed by replacing the top pins with smaller ones from your pin kit.
Another reason this problem occurs is because of the key code. A great difference in depth between 2 side by side cuts may cause unwanted friction within the core. Generally you can should avoid this in the key generating process. More on this in later chapters.
Cylinder is stiff to turn:
If the key turns the cylinder but the cylinder feels stiff to turn, this is usually because your bottom pins are slightly too large. To fix this, dismantle the core and try to identify the problem pins and then replace them with smaller pins. Note: you will likely not need to go down a full pin size down.Use your fingers to feel if it is flush. Don’t be afraid to get in close and look.
Sometimes on older locks, dust and accumulated junk gets in between the core and the cylinder and interferes with the rotation. Give a liberal squirt of penetrating into the keyway then insert the key and rotate it a few times. Repeat this process if necessary.
The last reason that your cylinder may be stiff to turn is also the worst. Sometimes during the rekey process a spring may come loose and become entangled in the sheer line. As the cylinder turns, the spring is uncoiled from the top chamber as it wraps around the core. To fix this how have to dismantle the cylinder and replace the broken spring. However, you might find that the entangled spring makes it difficult to remove the core from the cylinder. You will need to physically force the core out using the follower. From here you check all the top pins as if you were looking for master pins. Replace the broken spring and reassemble the cylinder.
Cylinder catches as it turns:
If the cylinder catches as it turns this is because the rekey was not precise enough. The sheer line is not being fully met and that creates a cleft of friction as the cylinder turns. To fix this you have to re-rekey the lock. Take your time. Use your fingers to feel if it is flush. Don’t be afraid to get in close and look.
An exploded cylinder is when the top springs and pins erupt out of the top chamber. This primarily occurs when you are removing the core, such as when you are rekeying, checking for master pins, or fixing broken springs. To fix this you need to reassemble the top chamber. Start by removing everything from the top chamber. Using your tweezers, place all the top springs into the top chamber. Insert the top pins by using the follower and your tweezers. Depress the top pin into the top chamber and slide over it with the follower. Do this one pin at a time until you have completely reassembled the top chamber. From here, rekey the lock starting with rekeying the cylinder.
As always, gaining familiarity and experience with rekeying locks will make you better at rekeying.