The mower will have at least two spindles that are placed apart from each other in specified dimensions. On each of these spindles, two blades of different lengths are mounted at different heights.
Each of the blades has horizontal clearance so that when it cuts grass, any parts left are cleared by the overhanging blade. This way, they both have enough space to rotate without colliding.
So, essentially, blades are timed to provide a horizontal overlap, but that does not interfere with their way of working.
On the second spindle, blades mounted take the route of the first two. They are on the same plane but of different heights to complement the first set that is mounted on the first spindle.
The first upper blade that is longer than the first lower blade is mounted much higher.
Its height matches that of the second lower blade, and the same logic is applied to the second upper blade. This enables them to sweep in circles without coming into contact with each other.
What Could be Causing Uneven Cutting?
If blades overlap perfectly, then they should not leave any uncut grass.
If you still aren’t able to maintain a clean cut lawn despite your efforts, then you may want to read on.
1. Failing to Overlap
When cutting grass, you want to ensure you overlap at the right dimension to get all the grass. There is a small gap between blades that you can only cover by overlapping the rows correctly.
When mowing, blades pull the grass up while tires press it back down. There is always going to be a strip left uncut as the grass has been pushed back too low for the blades.
To remedy this, you want to make a 7 to 10 centimeter overlap estimate, ensuring the next tire path is inside the previous one. This way, blades will be able to pull the grass up and cut it, leaving an evenly cut lawn.
You will also save time.
2. Damaged and/or Dull Blades
Blades don’t remain the same as they were bought, obviously, and so it is upon you to check on them every now and then.
Wear and tear causes them to get nicked, warped or curled over time, and this necessitates a complete overhaul.
If they are simply dull, which happens after regular use, then you should sharpen them.
How often – and for how long – should you sharpen your blades? It depends on how long you use them at each instance.
For motorized mowers, sharpen every 3 to 4 years if you mow your lawn for an average 15 minutes are each session. If a single mowing session lasts 30 minutes, then you want to sharpen your blades every other year, or roughly after 40-50 sessions.
Once or twice a year would work just fine if you mow for 1 to 1.30 minutes each time, while sharpening twice a year would be ideal for those who mow for over two hours each session. A sharp pair of blades is healthy for your grass too.
3. You Move too fast
Another possible reason for uncut patches on your lawn is speed. Do you move too fast when mowing? Then this could leave some parts untouched.
You want to slow down while at the same time ensuring your mower’s engine is working at full throttle as it is meant to. Slowing down will also ensure you check your progress as you work.
How to Take Care of Mower Blades
When blades are damaged, you have no choice but to replace them, which is a costly affair. You can ensure their longevity by dong a few things differently.
1. Pick up any Obstacles
Before you start working on your lawn, go round and ensure that nothing is in the way of your mower. Pick up any sticks, rocks, or anything that could hit your blade and cause damage.
2. Sharpen them
You don’t want to rush into replacement simply because your blades are no longer sharp enough. Sharpen them as per the sessions we have discussed above to avoid straining them unnecessarily.
When you take care of your blades, they cut evenly, save you time – as you will time the overlap just perfectly – and you save some money. Check on them regularly.