When sharpening a clipper blade there is a lot of things that can go wrong. The blade needs to have a hollow (concave) grind and in order to produce this discs which are used are machined to within very tight tolerances. The blades are sharpened using discs that are coated in a removable material that takes the smallest amount of metal off to produce the desired result. If blades have been sharpened poorly, they sometimes need multiple passes to restore the correct shape. Once the blade is sharp it is reassembled and the spring is tensioned to allow the optimal amount of movement to minimise wear on the clippers and maximise the blades cutting ability.
In the sharpening industry there are 2 main forms of sharpening that are used on grooming equipment; automated and free hand.
With practice it is theoretically possible to produce consistent results using the free hand method but as this has significant room for error it is better to use a machine that will produce the same result every time. We use a machine with full automation and we check EVERY blade that is sharpened to ensure there is a consistent rub pattern on the metal. We also check every blade on rabbit hair because if the blade can cut rabbit hair it will cut anything.
There are many sharpeners in Australia and overseas who still sharpen free hand and while the results can be good there is less consistency.
If the blade is not cutting there can be many reasons. The blade could have the wrong shape, flat instead of hollow, the spring tension could be wrong, the clippers could be worn out and the turning (drive) lever might not be sitting in the blades properly. It is difficult to tell where the issue lies but the best option is to send the blade to us and we can test it on equipment designed for this purpose.
There is a lot of misleading information online about how you can sharpen clipper blades. There are some very destructive videos that have been circling that show how you can sharpen blades on a piece of emery paper and this can lead to blades that are not only blunt but are so damaged that they cannot be sharpened properly anymore. PLEASE DO NOT use sandpaper to sharpen clipper blades! This changes the shape of the blade and results in significantly reduced blades life and can even mean that they are no longer able to be sharpened.
Here are some examples of the type of misinformation that is on the internet: