How Consumer Reports Tests String Trimmers
We evaluate both gas and electric string trimmers, including the battery-powered variety. To test how well each works, we tackle typical yard weeds and high grass as well as dense brush, noting and timing how long each model takes to clear a defined path.Ā We also test each string trimmer at edging, or its ability to create a neat and straight line along a walkway. And we look at how easy each machine is to hold, maneuver, and operate, noting how difficult it is to start up or feed extra line through the cutting head. For gas models, we note the ease of adding gas and oil (for those with two-stroke engines) as well as the ease of starting the tool with a pull cord.Ā
To find out how well the string trimmers in our tests perform, see ourĀ string trimmer ratingsĀ chart. There you can explore the pros and cons of more than 60 models, and filter for the features that fit your needs best.Ā
Curved or Straight Shaft?
A string trimmerās shaft is either curved or straight. Whatās easier to handle depends largely on personal preference. If youāve never used a string trimmer, try out both curved-shaft and straight-shaft models in a home center or hardware store to see which feels better for you.
CurvedĀ shafts (which tend to be shorter) allow the user to nimbly maneuver around obstacles, while straight shafts (generally longer) increase the userās reach and coverage from a given point. In general, pros favor straight-shaft models for this reasonāthey can cover more ground with fewer steps.Ā Ā
Which Power Source Is Right for You?
A string trimmer can be powered by gasoline, a battery, or a power cord, and all are capable of cutting well, depending on the model. So the best string trimmer type for your needs depends on your task at hand. Misha Kollontai, CRās engineer in charge of string trimmer testing, recommends choosing your power source according to the size and layout of your yard.Ā
Gasoline string trimmers work for a yard of any size.Ā Corded string trimmers are best for yards up to about 1ā4 acre. Battery-powered string trimmers make sense for a yard up to about a 1ā2 acre, but they can tackle much larger yards if you have multiple batteries that you can charge and swap in.
Other String Trimmer Considerations
Should You Buy a Powered Base?
With gas and some cordless string trimmers, youāll have the option of buying a stand-alone tool or a powered base, also known as a split shaft. This is an engine designed to accept different attachments, and itās typically sold with a string trimmer head. For most models, you can also get a hedge trimmer, a pole saw, an edger, and a brush cutter, and even a cultivator attachment. Itās a good option if you need a string trimmer and any or all of the additional tools, and you donāt want to buy each separately.
Mind the Gap
Before you buy any string trimmer, look at the cutting head, where it meets the shaft of the trimmer. If thereās a large gap, be warned that tall grass will probably get wrapped around the shaft in that spot. Instead, look for a model with a minimal gap, or one with an easy-to-remove cutting head so that you can quickly pop the head off and get rid of weeds.Ā
Safety First
String trimmers can easily break through skin. And while a shield deflects most debris, trimmers can still send debris flying while they cut. Wear gloves, protective eyewear, boots, and long pants. For gas models, use hearing protection, such as earplugs or earmuff-style headsets.
String Trimmer Types
Let your lawn and landscape dictate which type of string trimmer you buy.Ā
Gas-Powered String Trimmer
Traditionally theĀ best string trimmerĀ for large properties, a gas-powered model goes anywhere and can run indefinitely,Ā as long as thereās fuel in your tank.Ā Theyāre not as popular as battery-powered string trimmers anymore, but youāll still have plenty of options.Look for models with an adjustable handle and a translucent gas tank so that you can see when fuel is low. Gas-powered string trimmers with a four-cycle engine run cleaner and use regular gas but cost more. Models with a two-cycle engine cost less, but youāll need to add oil to your gasoline. All the gas-powered string trimmers in our tests are loud enough to require hearing protection (earplugs or earmuff-style headsets) for the user.
Cost: $70 to $390
Corded-Electric String Trimmer
Though corded yard tools may seem outdated, a corded string trimmer can perform really well for a certain subset of homeowners. If you have a small yard and donāt need to trim more than 100 feet from an outlet, these are ideal. Most have a short cord and require a long outdoor-rated extension cordāyou can typically find these cords in lengths up to 100 feet. Corded-electric string trimmers tend to be the cheapest of the three types, plus they start instantly and run indefinitely, and you donāt need to worry about buying gas or charging a battery.
Cost: $70 to $130
Battery-Powered String Trimmer
In our latest tests, the best cordless string trimmers cut as well as or even better than gas models. Plus they produce no emissions and run quietly. They also start instantly every time, without you having to fuss over the choke or yank a pull-cord. They require far less maintenance, and their batteries can typically be used in other outdoor power tools from the same brand, includingĀ lawn mowers, hedge trimmers,Ā leaf blowers, andĀ chainsaws. The life span of the lithium-ion batteries powering these tools is still a big unknown, so look for a long warranty (at least three to five years) that specifically applies to the battery. Expect to cut for about 30 minutes on a single charge. Most batteries take about an hour to recharge once theyāve fully drained.
Cost: $115 to $300
String Trimmer Parts
Shopping for a string trimmer can be confusing. Hereās the help you need to get the job done.
Shaft
The shaft transfers power from the engine or motor to the (typically hard but flexible nylon) lines that do the cutting. Models with a straight shaft offer a longer reach; they tend to be better for tall users and for reaching beneath bushes and other shrubs. Models with a curved shaft (shown) are typically lighter and easier to handle.
Rotating Head
On some string trimmers, the cutting head can be swiveled to a vertical position for edging. This feature is especially useful because the trimmer can otherwise feel unwieldy if you have to maneuver it 90 degreesāand hold that positionāfor several steps as you edge your lawn where it meets a driveway or sidewalk. Ā
Cutting Line
All string trimmer manufacturers will tell you the proper size required for your replacement line. Be sure to use whatās intended for your model. Line thatās too thin can compromise cutting power, while line thatās too thick can bog down a trimmerās engine or motor. Trimmers with two lines cut more grass with each revolution than single-line models do, so they can typically handle heavier growth.
Cutting Line Feed
You have three options: bump feed, fixed line, and auto feed. A bump feed releases line from a spool when you bump the trimmerās head on the ground. But more models are using fixed-line headswith short lengths of line to help eliminate the jams and tangles associated with loading new line: You simply thread in a piece of line as neededāthough youāll have to do that relatively frequently. (Fixed-line heads are also available as aftermarket items.) Auto-feed heads come pre-wound and release line on their own as needed. Ā
Starting Aids and Stop Switches
Spring-assisted starting makes pulling the starter cord of a gas-powered trimmer easier. And a relatively foolproof sequence of pushing the fuel-primer bulb and engaging the choke delivers the proper fuel mixture to a cold engine for faster starts. Trimmers that have the stop switch within easy reach let you quickly stop the engine or motor if you need to.
Shaft
The shaft transfers power from the engine or motor to the (typically hard but flexible nylon) lines that do the cutting. Models with a straight shaft offer a longer reach; they tend to be better for tall users and for reaching beneath bushes and other shrubs. Models with a curved shaft (shown) are typically lighter and easier to handle.
String Trimmer Brands
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