What is a Jimmy Proof Lock?

Jimmy Proof Locks are the cousins of the original Dead Bolt Lock. They are oval shaped with a flat side that incorporates a bolt which can slide up and down into the strike plate when the door is shut and in position.

The strike plate is a separate piece made of brass that attaches to the frame with self-tapping screws. The lock is also very easy to work with as it can be used on any side of the door regardless of the type of swing. Doors come with a few options for installers to consider when building the frame and it is usually in swing and out swing and or left handed or right handed.

What differs in these two types of locks are that the original dead bolt is a complete locking system as in comparison to the Jimmy proof which requires a rim cylinder for the lock to function. In Most cases you will find the Jimmy Proof Lock on the inside of an apartment building door. The reason why they call it a Jimmy Proof Lock is because of the lack of access to the outer portion of the Lock via the front of the door. In essence the purpose was to make a lock that cannot be pried off as there is no Lock on the outer portion of the door. The beauty of the lock is in its simplicity as it requires only a one inch and a quarter hole to install the lock in comparison to the deadbolt lock which requires numerous holes, four to be exact.

Jimmy Proof Locks are found and often used in major cities such as Brooklyn and Manhattan for a primary source of Security.

For a proper installation of a jimmy proof lock the following is needed.

First we need a drill. The drill can be powered or cordless. Next we will need a hole saw approximately 1 and 1/4 inch to drill a hole into the door to fit the rim cylinder. Then we need a quarter inch drill bit to put inside of the hole saw as we need to make a pilot hole for guidance of the hole saw and a screw driver with a Phillips Head Bit.

When unpacking the jimmy proof lock there should be a plate that attaches to the cylinder threw two holes that support screws. Prior to drilling any holes it is suggested that the frame housing the door is at least one inch in diameter as we need a place to attach the strike for the jimmy proof to lock. Assuming that you meet the above criteria, you will take the back plate that comes with the lock and you will hold the edge which is straight up to the edge of the door making sure that it is flush and completely straight and level with the door. You should notice that the plate has a large circular hole sitting in between the two screw holes that were mentioned above as this i going to determine where you drill your hole. Once it is set up, you will need a pencil to draw a circle using the large holes edges as your guideline. When this is complete i recommend taking a quarter inch drill bit to make a hole in the center of the circle prior to working with the hole saw. Once completed you can now take your hole saw a begin to drill your hole. I suggest choosing a low speed for metal doors and high speed for wood. When drilling try and make certain that the drill bit reaches the opposite end of the door so drilling can be completed from the opposite side as the hole saw often will not reach all the way through.

Now it is time for installation of the lock.

When removing the lock from the package you should be observant of its contents and place them in an area with no interference as the screws can be misplaced and difficult to find. When removing the contents of the package there should be approximately eight items. The lock, the back plate which was used to make the measurements on the door for placement of the hole for the cylinder, two screws, a cylinder with a removable collar , and a strike for the lock to secure to with its vertical bolt mechanism.

Take the collar and place it at the very top of the cylinder. This will be accomplished when the cylinder cannot be pushed forward and must remain in the same position. Next take the rim cylinder and slide it threw the hole until the collar that we placed at the top of the cylinder reaches the door and stops the cylinder from going any further into the hole in the door. Now take the plate that we used to determine and measure the proper placement of the hole and line it up so the tail piece that extends from the cylinder can go through the hole.

Now you must stop and take a look that all holes line up and there are three to look for. The first is the large hole on the plate for the extended tail piece, next there are two small holes that were preset to line up with the two holes in the rear of the cylinder so the cylinder can be fastened and set in place. At this point if the directions were followed properly everything should line up and now you can take the two screws that came with the lock and easily line them up with the holes in the plate and cylinder and gradually screw them in. When this is accomplished it will be time to install the lock.

Take the lock and hold in a position that enables you to have a clear view of the backside of the lock. This is important as the tale piece will slide into a hole the is rectangular in shape and it is just big enough to fit the tail piece. This can usually be found close to the side of the lock that is closest to the bolts and there is usually a little spring like mechanism that controls a door on the jimmy proof lock to let the tail piece slide threw. This is for security purposes. When you are ready take the lock with the door on the lock in the open position and gradually insert the tail piece threw the rectangular hole and push the lock towards the the door until it is flush and pressed firmly against the door.

The Lock is now ready to be fastened and secured to the door with four screws that are supplied with the lock. Take the strike prior to securing the lock and attach it to the lock with the bolt mechanism. This is achieved by locking the bolts threw the strike holes. The purpose of this is to allow you to make minor adjustments to the positioning of the lock prior to installation and this is achieved by resting the strike on the frame as if it were already installed. Once the desired position is achieved it is time to drill and fasten your first screw.

I recommend when installing the lock that you use a method which is called caddy cornering. Take the first screw and install it in the upper left hole of the lock making sure not to drill to deep as you can strip the hole (complete final screw rotation by hand with a Philips head screw driver). Then insert the second screw in the bottom right hole so both sides are secure from different positions. Continue to install the third and fourth screw until complete and now you are ready to secure the strike.

The strike should be attached to bolts prior to placement and once flush should remain in the locked position ( the door must be in the closed position). Once mounted and flush against the frame we can start to take the first screw which should be towards the top and offers easy exposure and begin to drill. Do not drill completely as you may strip the hole so as before i recommend completing the rotation by hand. Once complete open the lock ad test the door to make sure it closes and bolts to the strike. Assuming the installation went well we can continue to screw the strike into place to finish our installation. The same steps should be followed to achieve desired results and when finished you should have a completely functional Jimmy Proof Lock that was installed like a pro.

This is a Repost of my original content located at All Boro Locksmith Brooklyn