To keep your lawn and cover greens neat and tidy, you need a mow it. That takes care of the larger surface cover, and for the most part, that’s the extent that the usual homeowner will go to in order to tidy up their grass.
For the avid landscaper, though, that’s a half-done job that still needs that extra bit of finish: leveling the grass near the flower beds and fences where the lawn mower cannot reach them, and squaring off the edges of the lawn neatly against the pavement. That’s where a string trimmer comes in, and what a difference they can make to give your lawn that professional, finished look!
What is A String Trimmer?
A string trimmer has a long shaft, with a head at one end that rapidly spins as it is driven by a gas or electric motor at the opposite end. This head has one or two strings made of monofilament plastic sticking out of it, and these are called trimmer lines.
As the head spins, the centrifugal force makes the line stick out to the sides, and their high speed works to cut down grass blades quite easily, trimming them down to the right height. The long shaft and the small size of the head of handheld string trimmers make it easy for the user to maneuver the tool around fence posts and trees, under bushes, or near flower beds and patios.
String trimmers are also called whipper snippers, weed whackers, line trimmers or weed whips, depending on who you ask.
Most string trimmers have a release mechanism that lets the user release more monofilament lines from an internal spool when the trimmer lines get worn out or break off. To keep the bits of grass from being flung back to the tool user, a small shield covers one section behind the shaft to block grass and debris.
Choosing the Right Type of String Trimmer for Your Needs
Most string trimmers on the market today fall under two broad types – the shaft string trimmer and the walk-behind, or wheeled string trimmers. Wheeled string trimmers are all powered by engines similar to the lawn mower, and you generally have only the gas powered type to pick from. Shaft string trimmers, on the other hand, offers more variety.
For shaft string trimmers, you can pick from corded electric, cordless battery powered, or gas powered options. You can also choose from curved shaft and straight shaft string trimmers when it comes to handheld models, as well.
Curved Shaft Versus Straight Shaft String Trimmers
Curved shaft string trimmers tend to be lighter and easier to handle for most people since the curve of the shaft lets you hold the string trimmer at a comfortable angle while still keeping the lines parallel to the ground.
Straight shaft string trimmers, on the other hand, offer a longer reach. Taller users, or for landscapers who use string trimmers on decorative shrubs and bushes, will find the straight shaft easier to hold accurately.
Gas Powered Shaft String Trimmers
These handheld string trimmers have earned their name of weed whackers – they have tiny gas engines, but they are as loud as they are powerful. With a gas powered string trimmer, you have almost unlimited freedom as to how large of an area you can cover, as long as you have enough gas and string, of course.
Gas powered string trimmers give you the freedom to move around your property without an electric cord getting in the way. For larger properties, a gas powered string trimmer is often the best choice.
That said, these tools do need regular maintenance on top of refueling and reloading of the trimmer lines.
Features to Look for in Gas Powered Shaft String Trimmers
- Assisted starter and fuel delivery systems make it easier to get consistent, one-pull starts from your string trimmer engine. An electric start option makes it even better but these tend to be a rare feature.
- Air filters and purge features keep air and debris from the carburetor and fuel system, which lets the motor start easier.
- Anti-vibration systems reduce user fatigue, especially important for noisier two-stroke engines on string trimmers that you have to carry all day.
- Translucent gas tanks and oil level indicators let you see if fuel is getting low.
- Adjustable handles let you balance the weight of the engine with the rest of the tool better.
Gas powered handheld string trimmers can come with either a 2-cycle engine or a 4-cycle engine. Models that have a 2-cycle motor are cheaper, but you need to mix gasoline and oil at the right proportion before you can use them with your string trimmer.
String trimmers that use a 4-cycle motor run a bit quieter and cleaner, and they can use regular gas. They are also more expensive, and they generally weigh more, as well.
Whichever type of engine you have, keep in mind that they are loud enough and close enough to the operator that hearing protection is a necessity.
Corded Electric Shaft String Trimmers
Yard tools that have to be plugged in before they can work can be very limiting, but for homes and businesses that have indoor lawns or small corner gardens, a corded handheld string trimmer might make sense.
They are much quieter than gas powered trimmers, put out zero emissions, and they are also some of the cheapest string trimmers that you can buy.
Corded trimmers are also the lightest type of trimmer you can get, with no bulky gas tanks or heavy batteries weighing down the tool Plus, they are dead easy to start and have a virtually unlimited running time, as long as you stay in range of an outlet, that is.
Features to Look For in Corded Electric Shaft String Trimmers
Built-in cord retainer helps you manage the electric cord better as you use the tool.
Flower guards protect delicate plants from accidental trimmer contact
Adjustable ergonomic handle lets you adjust the balance of your trimmer, whether the electric motor is mounted on the handle end or near the trimmer head.
Rotating heads lets you change the angle of the trimmer to make neat lawn edges and vertical trims on decorative shrubs.
Most corded electric trimmers have short cords and are meant to run off a longer spooled extension cord – preferably one rated for outdoor use.
Battery Powered Shaft String Trimmers
These trimmers combine the clean and quiet operation that comes with having an electric motor, with the freedom given by carrying your fuel with you. Just like corded trimmers, cordless electric string trimmers run silent and emissions-free.
Keep in mind that the batteries that you use for these types of tools will usually require a larger Ah battery, especially if you have a large area to trim. I would recommend 4.0 Ah batteries and higher for larger areas and a minimum of around 2.5 Ah batteries for smaller areas. You may need multiple batteries to get the whole area completed in one day.
Features to Look For in Battery Powered Shaft String Trimmers
- Power usage settings let you use the tool at maximum power to deal with tough brush or thick growth, or dial it down to save the battery if you are just putting the final touches on that lawn edge.
- Extra rechargeable batteries are nice to have to give you the option of swapping between them, with one charging while the other is in use.
- Automatic feed spool ensures continuous work, without having to stop to bump the string head to pull out more trimmer line.
You will also pay a slight premium for a battery powered model, and some of these can get expensive indeed. If you already have a bunch of battery powered yard and power tools, you might be able to get a cordless string trimmer that can use the existing batteries you have, saving you some money.
Most battery powered trimmers have a running time of about half an hour before your battery runs out. Standard lithium-ion batteries take about an hour to get a good amount of charge, too.
Cordless trimmers make sense for small to medium properties especially in communities where you prefer not to disturb the neighbors, like a subdivision for example.
Walk-Behind / Wheeled Gas String Trimmers
Walk-behind string trimmers work very much like lawnmowers, except that you are still helping to control the head while the whole tool is supported by two wheels.
This gives you a more precise control of your trim, unlike with lawnmowers. Plus, they have a much greater cutting width compared to the handheld models, letting you take on large overgrown lots that will overwhelm a lawnmower in no time.
Walk-behind string trimmers are just like the handheld gas powered variety, except that they come with wheels, bigger engines, bigger heads, and bigger lines. They are made to handle the roughest of overgrown lots, without you having to risk a bladed tool.
Features to Look For In Walk-Behind Gas String Trimmers
- Large wheels with tires made of tough rubber or plastic let you take your trimmer to rugged terrain, even if it’s an overgrown dump littered with rocks or broken glass.
- Extra trimmer lines ensure even cutting and consistent results, plus it lets you cover more area before you have to change them. Some wheeled string trimmers carry four trimmer lines, others may have even more.
- See-through fuel tanks let you know if it’s time for a refill.
- Starting aids and stop switches lets you easily start even a cold engine, or quickly kill the power if you need to.
- Self propelled units are very nice to have and make larger projects a lot easier.
Wheeled trimmers have cutting widths of 22 inches or more, plus they go through grass blades or even thick growth like a hot knife through butter with four or more high-speed trimmer lines working on one spot.
Comparing String Trimmers
String trimmers of different types have their ideal applications. Electric string trimmers suit those who need a tool that runs quietly, while gas powered trimmers are the better choice for contractors looking to clear thick grass or finish trimming a large property in an afternoon.
Price for Your Budget
You can have an electric corded string trimmer at less than $50, and it will already serve you well for small jobs within range of an outlet. If you are a landscaper by trade, though, you may want to invest in a walk-behind model that can set you back $300 or much more in some cases.
Gas powered handheld models are mostly similar in price to battery powered string trimmers, although that could change in the future as batteries continue to drop in price.
Cutting Width
Cutting width is your main consideration if you are comparing two models of the same type. Electric string trimmers usually cut a swathe from 8 inches to 18 inches wide, and the same goes for gas powered handheld string trimmers. If you are simply finishing up a mowed lawn or straightening the grass next to the sidewalk, this is plenty for your purposes.
Walk-behind trimmers, on the other hand, can cut a strip 22 inches wide, making them efficient at taking on large areas of untamed growth.
About String Trimmer Spool Feeding Mechanisms
The trimmer line feed options of your string trimmer will have a major impact on your productivity with the tool.
The traditional option is a bump-feed release mechanism that pulls a length of trimmer line from a spool when you bump the trimmer head on the ground, and these features vary in performance – some work really well, while others may give you the occasional snarl or tangle.
Other models have fixed line heads, where you thread in and tie pieces of trimmer line as needed – this is the usual approach with walk-behind models, as well. This simple approach ensures that you have the trimmer line rigidly fixed in place, although you have to manually change them every so often.
Finally, auto-feed heads come with spools of trimmer line preloaded, and a mechanism gradually feeds out new trimmer line as the ends get ground out or broken.
Weight and Shape
For handheld string trimmers, weight is one major consideration you need to take into account. Electric string trimmers can be as light as five pounds, while 4-cylinder gas powered trimmers can tip the scales at 21 pounds.
For the shape, some people prefer the curved shaft, while others work better with a straight shaft. If you are in doubt, it’s always best to try both types for yourself before settling on one.
