Originally published April 2018 in Lawn & Landscape Magazine
Blade Sharpening Q&A with
Gerd Bauer II, Vice President, Magna-Matic Corporation
1.Why should mower blade maintenance be done in-house by all landscapers and mowing contractors?
Simple and frequent maintenance processes are best completed in-house for economic, quality control, and convenience reasons. Mower blade maintenance is a frequent necessity. The investment in proper equipment saves money by cutting out a service provider’s overhead costs and profit. When you control the quality of the maintenance process, it directly translates to the cut quality of the turf/lawn. Being independent from a service provider’s timetable and frequent pickup and drop-off of blades makes in-house maintenance convenient.
2.How does a mower blade cut?
A lawn mower blade cuts with centrifugal force like a CNC milling machine. It is a cutting method commonly called “fly cutting,” which is defined as multiple cutting tips rotating at a high-speed fed into a material. A high tip-speed is essential to the cutting performance of a lawn mower.
3.Why should I maintain my mower blades every 8-12 mowing hours?
Mower blade tips become rounded (dull) after only 8-12 hours of use. The radius will become exponentially larger the longer you mow past 8-12 hours. The amount of grinding required after 20 hours of use is overwhelmingly more. More frequent sharpening will provide an exceedingly better cut on the lawn, reduce/eliminate the need for double cutting, apply less load on the mower, increase blade life, and reduce sharpening time. A blade with rounded tips is tearing the grass rather than cutting it.
4.What is the most efficient maintenance process for a mower blade?
First, a blade needs to be inspected for fractures. To do this, the blade must be cleaned of the grass build-up and debris. If the blade is free of cracks or fractures, the straightness must be checked. The MAG-1000 Blade Balancer’s gauge rod allows a simple and accurate measure indicating if the tips are in the same plane. If it has been determined that the blade is fit to be serviced, the next step is sharpening.Ensure the sharpening method will maintain a consistent cutting edge angle and allow you to grind the edge until a new tip emerges. Next, the balance of the blade must be checked to ensure efficient rotation. An accurate blade balancer is required to do this step. Lastly, we highly recommend productionizing blade maintenance. For example: if you mow 8-12 hours per day have a set of blades per day for each mower. Complete all of your blade maintenance at one time to achieve the maximum efficiency.
5.How do I choose the best mower blade maintenance equipment for my needs?
When choosing equipment or methods for cleaning mower blades, ensure the method/equipment is safe, enclosed, quick, and efficient. Avoid methods that create more of a mess than they clean.
A balancer is an important measuring tool that must be accurate and provide you with a repeatable result. Never use a nail-in-the-wall-method or table top cone because they are not accurate nor are their results consistently repeatable. The MAG-1000 Blade Balancer has been produced for 60 years and is used by mower service centers, mower manufacturers, and blade manufacturers for balance quality control. There have been various copies worldwide over the last 60 years but the accuracy and repeatability of indication of the MAG-1000 and remains the industry standard.
When choosing a sharpener there is a long list of features you need to address. Can the sharpener be set to a specific cutting edge angle quickly and consistently such that every blade you grind has a consistent angle? Can it sharpen your specific blades? Some grinders have restrictions on how long a cutting edge can be sharpened. Can it sharpen curved cutting edge (mulching) blades or only (conventional) straight edge blades? Many sharpeners are not designed to properly sharpen mower blades but are simply modified grinders that can damage blades and/or remove material temper. Are safety guards included with the sharpener? Does the manufacturer of the sharpener offer an ergonomic stand and a dust collection solution for the fine metal dust so that your employees are safe from sparks and dust? Lastly does the manufacturer provide a fully integrated system for all the processes of maintaining a mower blade?