BLACK + DECKER STC1820 18V Cordless String Strimmer Review

The familiar BLACK + DECKER black and orange plastic doesn’t look premium, and I’m sure it wouldn’t replace a much more expensive professional trimmer, but it’s solidly built for home gardening jobs.

The rear handle has a nice ergonomic design with plenty of rubberised grippy plastic. The safety switch is just above the trigger and can be engaged on both sides, which makes it fine to use for left or right handed users.

The front handle can be adjusted by pressing the large locking button, but it doesn’t pivot around the shaft compared with the Ryobi OLT1832. It isn’t a “D” shaped front handle that offers lots of different grip angles, but I didn’t find it uncomfortable to use.

Switching from horizontal grass or weed trimming to horizontal edging mode is satisfyingly easy. You simply pull down on the shaft and spin it round. There are no buttons or latches to fiddle with or break.

The blade guard isn’t over sized on this trimmer compared with other similar trimmers. Measuring just 31 cm across, it means you can get right into awkward corners and up against fence posts.

You can also adjust the length of the shaft to make it comfortable to use, whatever your height. There’s 21 cm of extension, so you should be able to find a comfortable working position.

If you want to turn this grass trimmer into a fully-fledged lawnmower, you can buy yourself the rather clever looking CM100 mower deck. A wheeled platform that you drop the strimmer into, it transforms this handy little trimmer into an all-round garden tidying machine. It’s ideal if you haven’t got the space for multiple garden machines.

Where this strimmer really beats the competition is edging. The wheel on the back of the blade guard means the string is always at the right height for clearing out the sides of paths or pavers. It’s easy to keep it running in a straight line, more so than any other strimmer I’ve tested out.

The auto-feed system makes sure that there’s always enough line for cutting, and even though it’s a single string machine, it worked fine for me. The problem with even the best strimmer is how the line is wound around the spool. An auto feed system will not work if the line is tangled, so it’s a good idea to inspect the spool before and after use.

The 28 cm wide cut path isn’t the biggest, but it keeps it manageable for the tighter parts of the garden and means you can strim in between plants without chopping precious flower heads off. It’s a shame it doesn’t come with a flip down flower guard, but that’s a feature you only find on more premium trimmer tools.

To help your batteries last for longer, there are two power levels to choose from. The low power setting is fine for light work such as keeping an already neat lawn in trim, but it obviously struggles when tackling fully grown weeds or tough grasses. On power level one, it produces 5,500 rpm, and on power level two it increased to 7,400 rpm. It felt a bit underpowered in eco mode, but I was pushing the trimmer quite hard. For regular lawn manicures, it’s fine.

I used both power levels to see how it performed, but I would probably keep it in “turbo” mode for most jobs and sacrifice a little extra runtime. You could always upgrade the included 2.0 Ah battery for a larger one if you have a bigger space to work on.

I got around 25 minutes of runtime from this strimmer in power level two. It might not sound a lot, but it’s plenty for a small garden or patch of weeds with a relatively low capacity battery. And if runtime is important, you can squeeze out another ten minutes on power level one.

The version I tested out came with a 2.0 Ah battery and charger, but it’s also available as a “bare” tool to save you some money if you have these already.

The charger supplied with the strimmer is tiny compared with a lot of other 18 Volt chargers I’ve used in the past. It’s certainly easy to store away, but don’t expect fast charging times. It’s only rated to charge at 0.4 mA per hour, so it could take nearly three hours to top up the battery from empty to full.

So, unless you have a small enough garden to finish in 25 minutes, or you have spare batteries, be prepared to take quite a long break when you’re tidying up your garden.

Running at up to 96 dB, this is not a quiet tool, but it’s much quieter than my old, corded strimmer and it sounds less harsh compared to the Ryobi OLT1832. It’s not going to help your relationship with your neighbours if you tidy up the garden before 8am on a Sunday, but it’s not going to shatter any windows.

Exposing yourself to noise levels above 70 dB for prolonged periods of time can cause permanent hearing loss. Invest in a quality set of ear defenders and they’ll be comfortable and fully protective.

Even though grass trimmers are one of the safest garden power tools, you still need to be careful and wear the right level of personal protective equipment (PPE) during use. A decent set of safety glasses are essential to help avoid eye injury, and ear defenders are important to avoid hearing damage.

Whenever you strim a garden, the string line will pick up small stones or other bits of debris and fire them all over the place. The blade guard should stop them flying towards you, but make sure to keep the area in front of you person and pet free.

The same thing goes for any other cordless battery powered tool. Once you’ve bought into a family of batteries and chargers, you can save a lot of money buy buying bare tools. BLACK + DECKER produce a huge range of 18 Volt grinders, drills, and other tools that suit DIY jobs and DIYers budgets.

I was impressed by how well this strimmer worked for how much it cost. The 2.0 Ah battery isn’t huge, and the charger is sluggish, but you can always upgrade these parts later. The strimmer is more than capable enough for a medium size garden, and at this price it’s hard to complain.

I’ve been lucky enough to test out the best garden trimmers on my property, from expensive double line strimmers and heavy petrol powered cutters to affordable ones like this BLACK + DECKER STC1820, and they all have their merits. But I must say that this is one of the best ones I’ve used in this price bracket.

The main positive of this garden strimmer is that it is so easy to use. It’s light, it’s easy to handle, the edging guide wheel makes cleaning up borders a doddle, and it’s simple to change the working height.

If you’re looking for a heavy duty strimmer with hours of run time, this isn’t it. But if you get yourself a couple of spare batteries and you’re not in a rush to recharge them, it’s a fine machine to use in the garden. I will be using it to keep my garden borders looking clean and tidy for the foreseeable future.