How to copy a broken key

The key shall be placed on the working table with the fracture as close as possible. Carefully check whether the fracture is warped, cracked and fluffed, so that the two fractures cannot be closely connected. At this time, you should be careful to repair, until the two can be closely combined, there is no gap between them. If there is a raised sharp angle on the fracture surface, it can be filed with a file, as long as it can not damage the tooth shape of the wheel, it doesn't matter. If the fracture is cracked and prevents the fracture from being closed, the key of the broken wheel can be clamped on the vise and put back to the original position with a small screwdriver. If the fracture surface is warped, uneven or bent, the uneven part can be clamped on the jaw plane of the vise to restore the flatness by clamping. But pay attention not to use strong force, so as not to flatten them. Once slightly flattened, they will deform, not to mention close. After repairing the fracture, the two keys can be closely combined. At this time, a piece of wire and tape can be used to connect the two together. Now you can use the same key blank to copy the key. For the tooth profile at the fracture, you can file less and make it higher for later repair. At this time, insert the copied key into the lock for a try. If you can open the lock, you can repair the tooth shape at the fracture until the key can rotate smoothly in the lock.