IF you've ever lost your keys or had a scary breakup, then you know the importance of having to change your locks. In a less dramatic vein, loose doorknobs can also become a nuisance that need to be taken care of. Here's a short guide on how to tighten up and replace doorknobs.

Doorknobs generally become loose for two reasons: Either the beauty ring on the outside of the door behind the handle works loose, or the inner workings are worn out. Start by tightening everything up, and if the knob is still loose, I recommend kicking it to the curb and buying something new.

Replacing a doorknob is easy and requires few tools: a slot screwdriver, a Philips-head screwdriver and a butter knife should do the trick. First off, to keep thieves and robbers out, the handle on the outside of the door has no removable parts, so you will be working on the inside of the door.

Getting started

Begin by removing the knob. There is commonly a slot in the stem of the handle through which you will see a retaining tab. Depress this with a butter knife and the handle should then slide off.

Next, remove the beauty ring, which is pressure-fitted. There may be a slot on the side. If so, insert the slot screwdriver and twist to pop off. If not, carefully work your butter knife under the ring and pry. Hiding behind the beauty ring will be two screws holding the whole assemblage to the door. Carefully unscrew these. This can be a chore as the screws are long and oftentimes stubborn.

Once the screws are out, the entire assemblage will slide out from the outside of the door. What's left should be the latch and latchplate. Some latches have mechanisms inside the removable assemblage while others will remain in the door. Either way, unscrew the latchplate on the side of the door and remove.

It is easiest to purchase a doorknob that is similar to the one you are replacing. Take the entire assembly with you to compare with the one you are buying. Most hardware stores carry standard doorknobs, but if you're looking for something special, KHI Hout Construction Materials on Mao Tse-tung boulevard has a fairly decent variety of doorknobs and handles, and they can help you find something comparable.

To replace the doorknob, reverse the steps you took to remove it, screw in the latch and then screw in the handle. The beauty ring on the outside of the door screws in and out to adjust for the depth of the door and should be firmly fixed in place once the screws holding the assemblage have been tightened.