How to Identify Badly Cut Keys

Key duplication is generally something people get done as quickly, easily and cheaply as possible. But shortcuts like this can expose you to a whole host of issues. Not only can the quality of the key be sub-standard, but security can be compromised if the keys aren’t cut by the right people.

A duplicate key should engage the lock and turn easily – if it doesn’t, then it has been badly cut and you will probably need to get the original re-cut.

So Why Don’t Duplicate Keyword Always Work?

Well there are several reasons…

The wrong blank was used.

A key blank is a key which has not yet been cut to match a specific lock. It is basically the raw material used by locksmiths for duplicating keys.

Key blanks have ‘profiles’ which, in locksmith terms, refers to the squiggly line along the bit, or blade.

There are over 3,000 key blank profiles in Australia and selecting the right blank is vital for any successful key duplication – and this comes with experience. It is common for inexperienced locksmiths to use the wrong blanks simply because there are so many options available and they don’t have the expertise required to make the right decision.

Equally, unlike professional MLAA accredited locksmiths, most hardware stores will only stock the top twenty blank profiles which limits the possibility of finding the correct blank.

Hint: If you can’t even insert your key into the lock then it is likely that the wrong blank has been used.

It was poorly cut.

If you can insert your key into the lock, but it won’t turn properly, then the chances are it’s a poor cut.

Again, accurate key cutting largely comes down to experience. Key cutters who are not trained locksmiths often lack the required skills to consistently produce exact duplicates.

For example, one common problem is that the key only works when it is slightly pulled out of the lock. This is usually a sign that the key was mal-aligned with the cutting machine.

If the key fits the lock but won’t turn at all, this again indicates that the key was not placed correctly in the clamps, or jaw, of the key cutting machine.

If the key engages the locking mechanism of a lock (i.e. ‘bites’), but then spins loosely, this is commonly a mistake of cutting the key too deeply, whereas if the key bites, but is very stiff to turn, then the cut was too shallow.

The maintenance of key cutting machinery is also crucial to the quality of the cut; poorly-maintained equipment will impact the precision of the key duplication.

Most reputable locksmiths will not only use the latest machinery, but will scrupulously maintain their tools and equipment, to ensure accuracy – and happy customers!

Hint: If you can insert your key into the lock, but it won’t turn properly, then it’s probably a poor cut. The key profile, as well as the lengths of its’ grooves and shoulders should match perfectly with the original.

The original key was damaged, or worn.

A perfect key duplication is almost impossible if the original key was rusted, bent or damaged in any way. Even the most skilled of locksmiths would be unable to produce a perfect replica of an original key if the original was damaged or worn.

Hint: Don’t expect miracles! It’s nigh-on impossible to create a perfect duplicate of an imperfect original.

Worn key vs non-worn key
Worn key vs non-worn key

The duplicate key was cut from a copy of the original.

No matter how experienced the locksmith, a duplicate key will never be as good as the original key. Even good copies will pick up minor flaws along the way.

There are a number of variables which will determine how many generations a key will last, such as the quality of the original key and the accuracy of each copy. However, as a general rule, a key should last between four and six generations. Past that, the likelihood of a duplicate working is minimal.

Hint: Always duplicate an original key, rather than a copy of the original.

Using a professional locksmith in the first place will likely save you time and money in the long-run – even if you need to travel a little further to find one. This will also give you peace of mind that your security will not be put at risk.

If you need copies of any key, contact the friendly team at Lock, Stock & Farrell today! We also offer a 7-day emergency locksmith service for the greater Perth area.




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