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Contact Victor Aguilar for locksmith service and queries. Victor Aguilar is rated A+ by the Better Business Bureau. He has 25 years of experience as a commercial locksmith.

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Modification of Inexpensive Locks


  1. 1) At least two different sizes of top pins matched to the sizes of bottom pins..
  2. 2) All locks have one pin chamber with a shortest possible bottom pin and no master pin, and one pin chamber with a longest possible bottom pin. .
  3. 3) At least one pin chamber, but not all of them, has a spool top pin.


  1. 1) Having different sized top pins keeps the pin stack roughly the same length and thus puts about the same pressure on every spring. Too long of a pin stack crushes the spring and prevents the key from sliding in and out. Thus, a lock that has only one size of top pin must use a short one to avoid this problem when it is matched with a long bottom pin. But matching this short top pin with a short bottom pin results in too little spring tension, which makes that pin chamber insecure. A heavy Babe Ruth bump on a short bottom pin works only if there is also a short top pin and a loosely fitting spring; if the top pin is twice as heavy as the bottom pin and the spring has the correct tension, the two pins are not going to fly upwards and then spread apart.
  2. 2) Always cutting keys with shallow cuts reduces wear on one’s key machine and reduces time spent making keys. A lock with all very shallow cuts on the key can sometimes be opened with a heavy Babe Ruth bump, but a long pin (#7 in KW1 or #9 in SC1 locks) requires a granny bump. It is not possible to be Babe Ruth and granny at the same time.
  3. 3) The presence of a spool top pin has no effect on bumping, but makes the lock significantly more difficult to pick. In combination with rules (1) and (2), this rule is easily implemented by having the longer of the two available top pins be of the spool design and the other one standard. By (2), the pin chamber with the shortest possible bottom pin and no master pin will get a spool pin, but they cannot all have such short bottom pins because, by (2), at least one must have the longest possible bottom pin.

How to Modify an Inexpensive Lock The link above is to a PDF file of my proposed modifications so you can print it out and just hand it to your local locksmith. It is easy to verify that he follows rule (2) simply by looking at your new key and observing that it has one very shallow or no cut, and one very deep cut. You will have to trust that he also follows rule (1) by matching short top pins to long bottom pins and vice-versa to keep the pin stack length uniform. Also you will have to trust that he follows rule (2) by including at least one spool pin, probably a long one in the chambers that have short bottom pins.

These modifications cannot be expected to come free with the rekeying of a lock. So be sure to tell your locksmith up front that you are willing to pay extra – ten dollars per cylinder is appropriate –beyond the standard price of rekeying. If you just start dictating what you want him to do without mentioning money, he is going to get grumpy. If your local locksmith is an old greybeard who insists on doing things “the way they’ve always been done” (e.g. in the most labor-saving way possible), then I can sell you locks by mail order.

Inexpensive Replacements

In the previous column, I reviewed packaged sets of both a deadbolt and knob, which made sense because manufacturers make both so they both needed to be reviewed and buying them as a set eliminates the cost of rekeying them to match. However, for people concerned about security, entrance function knobs are always a weakness. Neither Defiant nor Schlage cylinders can be pulled out of knobs with the ease of Kwikset, but a heavy hammer blow will take either brand of knob right off the door. Then the cylinder can be taken to a locksmith to be decoded and the thief can return to open the deadbolt with the key.

Thus, my first recommendation for a replacement is actually to a less expensive lock than what you currently have: replace the entrance function knob with a passage lever. Kwikset passage knobs are crap intended for unused interior closets and will never stand up to daily use on your front door. Just because it does not have a key does not mean that it is not suffering wear from being opened every day. Schlage and to a lesser extent Defiant make fairly durable passage levers that will work for exterior doors.

Next, if you can afford them, replace your existing Kwikset or Defiant deadbolts with Schlage. Schlage deadbolts are heavier duty and are still considered inexpensive, though they are pushing the upper limits of this price category. Schlage SC1 keys are incompatible with Kwikset and Defiant KW1 keys, so if you make this switch you must replace all you deadbolts. This switch is easier for people in apartments with one entrance door than for people in houses with many exterior doors. Save you existing lock so you can put it back on when you move out. Your landlord will probably want a copy of the key so they can enter in case of a water leak or similar maintenance problem.

Modifications to the Door

When a door is kicked open, one of two things happens:

  1. 1) The lock rotates through the wood around the bolt. The bolt is 1” in diameter and the door is 1¾” thick, so there is only ⅜” of wood on either side of the bolt. The wood just splitters away allowing the bolt and to some extent the entire lock to rotate until it comes free from the strike plate.
  2. 2) The door frame is only ½” thick and, if the strike plate is attached only to the frame and not to the 2X4 behind it, the frame will split through its entire length and allow the bolt to come free of the strike plate.

Burglars usually kick the lock side of the door because they are used to doors opening this way and because the lock gives them an aiming point for their foot. However, more sophisticated burglars kick the hinge side, especially if the deadbolt appears to be heavy duty and/or there are visible plates to reinforce the wood around the lock. They know that people almost never reinforce the hinge side.

Thus, there are three modifications that I recommend to strengthen doors from kick-in attacks:

  1. 1) Install a Mag Plate around the deadbolt. (Neither Kwikset, Defiant nor Schlage comes with such plates.) MagLock makes one in the same color as satin nickel Defiant locks and the combination looks nice enough for a front door. If this is a new installation, then drill a 1½” hole – not the more common 2⅛” hole – and buy a Mag Plate with this smaller hole.
  2. 2) If your deadbolt does not currently have a large strike plate with long screws, install an after-market one. MagLock makes superior after-market strike plates. Defiant is slightly better than Kwikset and Schlage is comparable to MagLock if it is installed correctly; lazy locksmiths who install Schlage locks often throw away the security strike and just install the decorative trim plate with ½” screws, which is really fraud because the customer bought a Schlage and expected to get all the parts.
  3. 3) On the hinge side, a locksmith can install long screws that extend about an inch out and then he can cut off the heads. He then drills holes in the edge of the door to accept these protrusions and to allow the door to close fully. This makes the door as strong as it can be; the next step is to buy a solid wood door, though this goes beyond the “inexpensive” category of modifications.

A further modification is to install a peephole with a 1” hole and glass, not plastic, lenses. MagLock makes such a peephole. This allows you to see outside with your head a couple of feet back if you move it from side to side. The person outside cannot see an image through the peephole; but he can see light and, if it suddenly goes dark, he knows that your head is directly behind the peephole and he can shoot you through the door. The cheap ½” diameter peepholes with plastic lenses require you to put your eye right up to them.

Some gun magazines have promoted the idea of a “safe room,” usually the master bedroom, where the family can retreat to in the event of a home invasion. Interior doors are basically just two sheets of stiff cardboard, so installing a deadbolt is pointless. Solid wood doors do not come in this smaller size, but the hardware store will cut one down to size for you. Purchase one without decorative indentations because, when it is cut, the decorations will be off center. Having made this purchase, all of the modifications listed above can be made to this interior door. Because of the need for a new door, this is not an inexpensive project.

Securing the Patio Door

The little hardware store locks that mount on the inside and project a bolt into the floor provide more security than a wooden dowel, but I sell a better lock that attaches to the inside side of the door and clamps securely to a matching piece on the frame. It is over twice as expensive as the little hardware store locks, but much more secure. It does not provide key operation from the outside.

The heavy duty patio door lock is a good thing, but by far the best way to improve the security of your patio door is to move to an upstairs apartment. Walking up stairs is good exercise so, unless you are in a wheel chair or you have decrepit elderly relatives living with you, there is no good reason to live in a downstairs apartment. Most apartment managers will let you move from one apartment to another within the same complex at no cost and without breaking your lease.

A townhouse – a row of apartments attached side-by-side with the wooden doors facing a lawn and patio doors facing an alley where the people park their cars – is by far the least secure architectural design. If you live in a townhouse and are concerned about security, you do not need better locks, you need to give your landlord notice. There is no patio door lock with a key operation from the outside that provides any security; neither are they reliable. Patio doors were never intended to be one’s primary entrance; the engineers who designed them for upstairs balconies would be appalled to see you entering through yours with a key. Also, the wood door on a townhouse is insecure because it faces a lawn that nobody uses, so burglars can bump your lock until they are blue in the face, confident that they have an easy exit if somebody investigates the noise. Townhouses that have wood doors facing both the lawn and the alley are better, but an upstairs apartment is really the most secure architectural design.

Sneak Peek! In my next column I will review upscale house locks and find them wanting. You are better off modifying an inexpensive lock, as described in this column, than spending money on an upscale house lock. But, even if you have already made this decision, you need to read my next column to justify your choice to those who promote these upscale locks, and they do have their fans. Also, one of the three upscale locks can be modified in the same way that these inexpensive locks can be, so people who can afford it may obtain both a nice looking lock and reasonable security.

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