How Does a Standard Key Machine Work?

Updated on August 29, 2013

This article does not review or recommend models of key machines or discuss various types of key machines, but simply discusses how a traditional key machine with a cutting wheel works.

Kaba Ilco model 045 HD Key Duplicating Machine
Kaba Ilco model 045 HD Key Duplicating Machine | Source

Ah, the sound of brass being cut by a carbide steel rotating blade. If you've ever gotten a key cut you know the sound is just not pleasant. However it is unique. Nothing sounds quite like it. And if you listen to it long enough with no ear protection that's exactly what you'll hear: nothing.

Yet it is fascinating, isn't it? This screaming little piece of equipment. Looking closer it is really a marvel of mechanical engineering.

Above is a picture from a brochure advertising key duplicating machines made by Kaba Ilco. This particular key machine is probably not much different than the first key machine ever made. It is certainly safer to use, but its operating principals are the same.

Below I have designed my own key machine with no shielding to protect the user from losing a finger or getting a brass filing in the eye. I did not design it for any other purpose than to illustrate how a key machine works .

Source
Key Blank vs. Original Key
Key Blank vs. Original Key | Source

Sum Of Its Parts

The above illustration is of a key machine designed to cut keys for everyday pin tumbler locks. Like all such key machines it has:

  • A means of turning the cutting wheel (in this case an electric motor)
  • A cutting wheel
  • A vice to hold the key blank
  • A vice to hold the original key
  • A guide
  • A key alignment device

NOTE: The following describes how a key machine is used. DO NOT use this paragraph for directions on how to use a key machine. BEFORE you use a key machine, consult the manufacturer's instructions and READ ALL SAFETY PRECAUTIONS CAREFULLY.

To use the key machine, an original key is inserted into the vice that is near the guide and a key blank is inserted in the vice near the cutting wheel. Using the alignment device, usually two bars that are connected to ensure they always remain the same distance apart, the keys are horizontally aligned in the vices to be in precisely the same place in relation to the cutting wheel and guide. The motor is energized and spins the cutting wheel. As the user traces the guide along the cuts of the original key, the key blank is dragged along the cutting wheel, duplicating the cuts on the original. When all the cuts have been cleanly made the process is complete.

After the key is cut, burrs are removed usually by buffing the key with a rotary wire brush either mounted on the key machine itself or on a grinding machine.

Below is another illustration of the key machine I designed just now, a little closer up.

Source
Source
Source

Key Alignment

The above illustration shows the key blank and original key inserted in the vices of the key machine and the alignment device in place, shown in red.

A key factor (if you'll pardon the expression) in cutting accurate keys is alignment of the key blank in relation to the original key. The cutting wheel is in a fixed position, but the guide can be adjusted in or out to compensate for the gradually wearing away of the cutting wheel during the course of duplicating thousands of keys. Keys and key blanks are fully inserted into the vices so that their backs are against a ledge inside the jaw of each vice, therefore their relative distance from the cutting wheel is the same.

Side-to-side alignment is achieved through the use of an alignment device - usually milled from a single piece of steel with two arms. The key and blank are slide sideways in their vices until both of their stops rest against their arm of the alignment device. Therefore the key and blank are aligned so that they are precisely the same distance apart as the cutting wheel and guide.

Above at right is a close up of a key blank inserted in the vice with the stop of the key resting against the alignment device.

Below is an illustration showing the relative position of the almost completed duplicate, the original key, the cutting wheel and the guide during the key duplication process.

Source

"Perfect"

The more precisely a key can be duplicated, the better the duplicate will work in the lock. Variables that affect precision in the key duplication process using a machine with a cutting wheel are:

  • Key blank quality
  • State of the original key
  • State of the cutting wheel
  • Adjustment of the guide
  • Skill of the operator

Key blanks are made by many companies in many countries. Most countries use the metric system whereas other countries use fractions of an inch. A discrepancy of 1/1000 of an inch can affect key performance; a difference of 3/1000 of an inch can mean that a duplicate will probably not work in the lock. High quality blanks are milled to precise specifications that match the manufacturer's original. The best blanks are usually made by the manufacturers of the locks that the blanks are made to fit.

Keys and locks grow old together. Insertion of a key produces friction, and friction produces wear. Pin tumblers and keys are usually made of a softer metal such as brass. As your key gets old you can observe that the peaks and valleys of the cuts are no longer sharp, but have become rounded. The same thing has probably happened to the pin tumblers inside your lock. In addition, all sides of the key wear away, making the original gradually shrink over time. All of these factors affect the ability of the key machine to duplicate the original accurately.

Key machine cutting wheels are made of carbide steel - much, much harder than the brass and nickel-silver key blanks they cut. That's why a cutting wheel can be used to cut thousands of keys and they will all be within close enough tolerances to work properly - until one day they are not. Cutting wheels get dull over time just like any other cutting tool, and when they do, the critical alignment necessary to duplicate keys is compromised.

For a while one can compensate for cutting wheel that is becoming worn by adjusting the guide. As the cutting wheel nears the end of its life it becomes smaller. Therefore the guide can be moved away from the vices slightly to compensate; however, as the wheel wears the cutting edge also becomes wider. No adjustment can compensate for that, so at that point the cutting wheel must be replaced.

Key machine operator skill varies widely. Some have no clue what they are doing at all, having had only some rudimentary instruction that has left out the important details of why copies of keys work and why they do not. Others are highly trained technicians who know absolutely everything about duplicating keys. It's kind of like Forrest Gump's box of chocolates: You never know who you are going to get.

Tips for Getting Accurate Key Duplicates

Well, for starters, go to a place that guarantees their keys will work. At least then if it doesn't work you can return it and have them try again or you can get your money back.

Try to get the original original. Look at your lock and find the name of the manufacturer. The name of the manufacturer will usually appear on the original key. If your key has the name of key blank manufacturer rather than the name of a lock manufacturer, you do not have an original key, but only a copy. Copies of copies rarely work as well as a copy of a genuine original key.

Ask your key duplicator to use manufacturer's original key blanks. Many key duplicators can provide manufacturer's original blanks. When you start out with the manufacturer's original blank, you have the best chance of getting the most accurately cut key.

Choose a key duplicator who has an array of key machines. If a key machine operator operates many key machines s/he must have an understanding of the key cutting process. A person who understands the process will most likely cut a better key.

Replace worn locks when they first start to give you trouble. If you are getting keys cut by a competant key cutter on good equipment using manufacturer's original blanks and you are consistently getting bad results, chances are it is either your lock, your key, or both that are the issue. It very well could be a signal that it is time for you to replace your lock and get new keys.

Questions & Answers

    © 2013 Tom Rubenoff

    Comments

      0 of 8192 characters used
      Post Comment

      • Tom Rubenoff profile imageAUTHOR

        Tom Rubenoff 

        4 years ago from United States

        Thank you, Epbooks!

      • epbooks profile image

        Elizabeth Parker 

        4 years ago from Las Vegas, NV

        This was an excellent, well-written and informative hub. I won't be buying a key machine at all, but for those who have one, these instructions are perfect!

      working

      This website uses cookies

      As a user in the EEA, your approval is needed on a few things. To provide a better website experience, dengarden.com uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

      For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at: https://dengarden.com/privacy-policy#gdpr

      Show Details
      Necessary
      HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
      LoginThis is necessary to sign in to the HubPages Service.
      Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
      AkismetThis is used to detect comment spam. (Privacy Policy)
      HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
      HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
      Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
      CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
      Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the googleapis.com or gstatic.com domains, for performance and efficiency reasons. (Privacy Policy)
      Features
      Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
      Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
      Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
      Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
      Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
      VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
      PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
      Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
      MavenThis supports the Maven widget and search functionality. (Privacy Policy)
      Marketing
      Google AdSenseThis is an ad network. (Privacy Policy)
      Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
      Index ExchangeThis is an ad network. (Privacy Policy)
      SovrnThis is an ad network. (Privacy Policy)
      Facebook AdsThis is an ad network. (Privacy Policy)
      Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
      AppNexusThis is an ad network. (Privacy Policy)
      OpenxThis is an ad network. (Privacy Policy)
      Rubicon ProjectThis is an ad network. (Privacy Policy)
      TripleLiftThis is an ad network. (Privacy Policy)
      Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
      Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
      Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
      Statistics
      Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
      ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
      Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)