How to Use a Cordless String Trimmer for the First Time

Before you start: gear and safety

A string trimmer throws grass, dirt and small stones at high speed, so protection comes first. Even a quiet cordless model can launch debris at your eyes and shins.

Some kits include goggles and gloves. For example, the HortiHub lists impact-resistant goggles and the ALSO GO lists gloves and goggles. If yours does not, buy safety glasses or goggles rated for impact before the first use.

• Eye protection: wear goggles or safety glasses every time the head is spinning.
• Clothing: long pants, closed shoes or boots, and gloves if you like a firmer grip.
• Hearing: battery models are quieter than gas ones, but earplugs or muffs are sensible for long sessions.
• Clear the area: pick up stones, toys, wire and dog bowls, and keep children and pets well away.
• Battery: keep it out of the tool while you adjust, clean or change line.

Set up the trimmer for your body

Most cordless trimmers need little assembly. You usually clip the shaft sections together, attach the guard, and fit the battery. Read the manual for your model, because the guard must be in place before you cut anything.

Next, adjust the fit. Many models have an adjustable handle or telescoping shaft. The ALSO GO, for instance, lists a shaft that adjusts from 33 in to 47 in. Set it so you can stand upright with the head resting near the ground and your arms relaxed.

Weight matters here too. On the page we compare, listed weights run from 3.28 lb to 7.8 lb. A heavier model often carries a bigger battery, so it can run longer, but it tires your arms sooner. If you are still choosing, our best cordless string trimmer comparison lays out weight, battery energy and swath side by side.

Check the line before the first cut

The cutting line is the part that actually trims, so make sure it is the right length. Some trimmers ship with short line. The HortiHub listing says to extend the line to 6 inches before first use. Check your own manual for the correct length.

Also learn how your line feeds. Auto feed releases more line for you. Bump feed needs a light tap of the head on the ground. Push-button designs advance line when you press a button. Knowing which you have avoids confusion mid-job when the line wears short.

If the line is too short, the trimmer cuts poorly and can strain the motor. If it is too long, it can slow the head and make the cut ragged.

Basic trimming technique

Take the steps below in order. They work for most cordless trimmers, though your manual always takes priority.

Once you are comfortable, the motions become automatic.

• Stand with feet apart, with a firm two-handed grip. One hand holds the handle with the trigger. The other holds the front grip or shaft.
• Fit the battery, release any safety lock, and squeeze the trigger. Many models use dual safety controls to prevent accidental starts.
• Hold the head roughly parallel to the ground, a few inches above the grass, with a slight tilt.
• Cut with the tip of the line. Use only the end of the spinning string, not the whole circle.
• Work in short sweeps. For taller grass, trim from the top down in stages instead of cutting at ground level straight away.
• Release the trigger and wait for the head to stop before you move, set the tool down or walk away.

Edging, fences and tricky spots

Edging along a walk or driveway usually means turning the head so the line spins vertically. Many models convert to an edger, such as the goodjob, HortiHub and ALSO GO from our data. Others pivot the head instead. The goodjob lists a 180° pivoting head for use under fences and around trees.

Go slowly near hard surfaces, because line flicks stones and grit outward quickly. Keep the guard between you and the target.

Be careful around young trees and shrubs. Repeated contact with the line can damage thin bark, so use a hand tool or a protective guard close to trunks. Also avoid cutting near metal fences or wire if you can, since the line wears fast against them.

Choosing a size and power level for the job

For a first trim, a modest model is easier to control. A wider swath covers more ground per pass, and thicker line handles tougher weeds. Here are some figures from the products on our page.

The table shows how a few of them differ. Pick the trade-off that suits your yard.

If you already own a trimmer and just need guidance, skip ahead to technique. If you are comparing models, our cordless trimmer rankings show which ones list runtime, since only some do.

Care after the job

Remove the battery before you clear grass from the head, change line or inspect the guard. A trimmer that starts by accident can injure your hand.

Wipe off clippings and let the tool dry. Store the battery indoors at room temperature when you can, and follow the charger instructions. Do not charge a damp pack or leave it connected after it is full unless your manual allows that.

Check the line length and the guard before each session. Small habits like these keep the tool working smoothly.

Frequently asked questions

Should I trim wet or dry grass?

Dry grass is better. Wet clippings clump on the head and guard, and wet ground makes slipping more likely. Also keep the tool away from standing water.

Which direction should I move the trimmer?

Check your manual. Many trimmers throw debris to one side, so move in the direction that sends it away from you and from windows, cars and walkways.

Do I need a second battery?

Not always. A second pack helps on larger lawns because you can swap and keep going. The HortiHub, goodjob and ALSO GO kits list two batteries.

Can a cordless trimmer cut thick brush?

Line trimmers suit grass and light weeds. Thick woody stems need a different tool, so check what your model is designed to handle.