Black & Decker 36V CLM3820L2 Cordless Lawnmower Review

Black & Decker 36V Li-Ion Cordless Lawnmower Body.jpg

Cordless battery powered electric lawnmowers have certainly become serious products for the well established garden appliance brands. This is the top of the line Black & Decker cordless lawnmower, simply named the 36V Li-Ion (model number CLM3820L2) in reference to its battery or batteries depending on the version of the lawnmower you purchase. We have the version which comes with two 36V batteries in the box.

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Design & Features

Black & Decker have definitely designed a 'looker' of a lawnmower if there ever was such a thing: your neighbours will look over in envy at the design and then wonder what kind of crazy witchcraft is powering your lawnmower. Their trademark orange and black design scheme plays well with the harmonious simplicity of the main body. It doesn't just look good, it also has some witty features.

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The height adjustment mechanism has six cutting heights (30mm-80mm) and is blissfully easy to operate via the lever located on the side of the mower. We also really liked the fact that the handles can be folded quickly by releasing the locks on either side, so the mower takes up less space in your shed or garage, and this also makes carrying it with the integrated main body handle easier - if a workout at 15KG. The handle is padded in foam, keeping your hands comfortable whilst mowing, and from our intensive usage the handle has remained firm and sturdy and refuses to wobble in use. Of course, this isn't a self-propelled lawnmower, but the larger rear wheels, in contrast to the front ones, make it very smooth to push up slopes, along textured terrains and, most importantly, it glides along flat grass lawns. Quality of plastics used are excellent too and easy to clean. The chassis surrounding the 38cm cutting blade is reinforced with thicker plastics than the rest of the body for that extra strength when cutting rougher terrains.

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Cutting The Chord

Removing the chord has many advantages, no cable to accidentally run over and cut, no cable to trip over, no frantic attempts to untangle the extension lead, no cable to get tangled up in, no cable to put away and no cable to restrict the boundaries of where you can cut. With regard to safety, the Black & Decker 36V Li-Ion lawnmower requires a key to be inserted into the handle start button fixture in order to power up the mower. Another benefit is that this thing is quiet, at 96 decibels, great for folks who like to mow their lawns ridiculously early in the morning.

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The quality of the cut offered from the Black & Decker 36V Li-Ion lawnmower is refined and even. It doesn’t pull up the grass and doesn’t leave wheel lines (we personally like a bit of striping) and does cope with cutting through damp grass, tall grass of 7cm-14cm, sticks and knotted weeds. But this mower can act finicky on uneven ground and the motor comes to a halt if the mower cuts into ground or tight grass roots if the cutting height is set low (we assume a safety feature) which can be irritating. It manages to scoop up everything into its 35 litre grass box (slightly better at doing so than the Einhell Power X-Change Cordless mower) and has a built in indicator flap which will stop blowing upwards to alert the user when it is full with grass. If you’d like to redistribute your grass, simply remove the grass box and the clippings will travel downwards from the back of the mower onto the ground you’re cutting. The performance the Black & Decker 36V Li-Ion boasts is exceptional and is a competent replacement for unclean and noisy petrol lawnmowers.

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Battery Life

From our testing, both batteries combined delivered a lifespan of around 35-40 minutes of cutting time, which is basically identical to the Einhell Power X-Change GE-CM 36 Li cordless lawnmower we’ve previously reviewed that also shares a similar design scheme to this mower. The only downside is the range of battery life for those with very large lawns. If you are one of those people with lots of grass to cut, you would have to spread the work over the course of a day. Furthermore each battery takes a lot longer than the specified time of an one hour a battery to charge once they've been operated and are hot. Unlike the offering from Einhell, which uses two 18V batteries simultaneously to gather 36V power, the Black & Decker uses one at a time. So you can have somewhat of a relay system in operation for better reassurance of range, but larger lawn owners will have still have to wait around.

Each battery has a built in LED indictor so that you can see how much charge is available from the press of a button, but they do fade in performance from the last few minutes of charge. Black & Decker also have a family of cordless tools that use the exact same batteries and vice versa and you can purchase them without the batteries and chargers supplied to save money. And the prices of tools without batteries can also be cheaper than the equivalent corded tools, so it's definitely a fantastic encouragement to continually go cordless once you're invested into the system.

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Black & Decker have had a few stabs at cordless lawnmowers over the years. This would appear to be their best and most refined attempt yet, with a design that just makes a whole lot of sense. The 36V Li-Ion CLM3820L2 is a genuine £399 alternative offering the same freedom that petrol mowing brings but with the cleanness and hassle free functionality of reliable electric power.

Four stars