The blades of a hedge trimmer should be sharpened approximately once after every 50 hours of use to maintain a decent quality of performance. To make sure your hedge trimmer stays performing well, you should keep up with sharpening and not wait until your blades are in too poor of condition to work properly. A dull or damaged blade will leave your hedges uneven and unhealthy after a trim.
Things to Keep in Mind Before You Start to Sharpen
Before you begin to sharpen your hedge trimmer, you should make sure to clean the blades thoroughly. Cutting branches may expose the blades to sap and resin or other material you won’t want present while sharpening. If you don’t thoroughly clean the blades first, you risk damaging the file and stone during the process. While sharpening, you should also always make sure to only sharpen the cutting edge and not let the file or sharpener touch the integrated cut protection; on professional hedge trimmers, this cut protection is the orange plastic piece.
Step One: Sharpen the Blades with a Flat File
A flat file or hand file can be used to sharpen the blades of your hedge trimmer. To make the process easier and quicker, make sure the top and bottom blades are resting in the same position before you begin. Flat files and hand files are designed to cut in the direction of the cutting edge to guarantee a quality cut for optimal performance of your sharpened hedge trimmer. Never bring the file in contact with the blade while moving it back upward, as this can cause the blades to become blunt.
In the manual that came with your hedge trimmer, there should be specified angle (listed under “Specifications”) at which you should sharpen the blades; make sure to maintain this angle while sharpening at all times. Also, you should be careful not to file away too much of the blade, as this could diminish the performance of the hedge trimmer. The wear threshold for hedge trimmers is 5mm, so sharpening should not go beyond that point. While filing, maintain the same amount of pressure so that each blade stays the same length.
Step Two: Remove Any Burrs with a Sharpening Stone
After you have sharpened your hedge trimmers appropriately, you should find any burrs on the bottom of the sharpened blade and remove them with a sharpening stone. Burrs are rough edges or ridges left on metal after sharpening with a tool or machine. After you have completely finished sharpening the blade and all rough edges have been removed, you should clean off the swarf. The swarf are little pieces or filings of metal that have been left behind during the sharpening process.
Finally, when the entire process is complete and the blades have been cleaned of any remaining swarf, you should use a spray to protect the blades. There are many spray products available that can remove resin and dirt while also lubricating the blades and protecting them from corrosion and rust. These sprays are incredibly useful and can help extend the lifespan of your hedge trimmers by a long time.
How Often Should You Sharpen Your Hedge Trimmer
Similar to the same question regarding lawn mower blade sharpening, the appropriate frequency of sharpening depends mostly on how often you use the hedge trimmers. Generally, there is no specific frequency you should follow; instead, sharpen the blades whenever it is clear that it is necessary. When you see that what you are trimming is being torn or left uneven instead of being cut evenly, it’s time to sharpen the blades. If you have purchased a used hedge trimmer, it is most likely necessary to sharpen the blades. Often people decide to sell the machine because they feel it isn’t performing as well as it used to, reason being the blades just need a quick file. This is a great opportunity for you to pick up a great deal.
Doing It Yourself vs. Bringing it to a Professional
There are professional services available that can help sharpen the blades of your hedge trimmers for you. Although you can definitely tackle such a task on your own, sometimes it may be better to let a professional handle it. Don’t let them talk you into buying a new hedge trimmer, because after a relatively cheap sharpening job the machine is as good as new. If you don’t have the patience or tools at your disposal, it may not be worth it for you to purchase them just for your hedge trimmers.
With that said, you may not want to keep bringing you hedge trimmers out to a shop every month if you use them that often. Depending on the frequency you need to sharpen them, purchasing the tools necessary to sharpen them yourself may very well be worth it.