How to String a Dewalt Battery Weed Eater? FlexVolt & 20V

Introduction

Dewalt’s cordless battery weed eaters are a top choice for homeowners and landscaping professionals alike, offering the power and convenience of cordless operation without the hassle of gas engines or tangled extension cords. Over time, the trimmer line on your weed eater will wear down, break, or become too short to cut effectively, leaving you wondering how to string a Dewalt battery weed eater? The good news is that restringing your Dewalt weed eater is a simple, 5-minute task that requires no special tools or professional help, whether you own a 20V MAX or FlexVolt model. This comprehensive guide will walk you through every step of the process, share tips to extend the life of your trimmer line, highlight common mistakes to avoid, and answer frequently asked questions to keep your yard looking neat all season long.

Table of Contents

• Understanding Your Dewalt Battery Weed Eater
• Tools and Materials You’ll Need
• Safety Precautions Before Starting
• Step-by-Step Guide to Stringing Your Dewalt Weed Eater
• Comparison of Dewalt Weed Eater Stringing Systems
• Tips for Longer Line Life and Easier Stringing
• Common Mistakes to Avoid
• Frequently Asked Questions
• Conclusion

Understanding Your Dewalt Battery Weed Eater

Dewalt offers two primary cordless battery platforms for their weed eater lineup: the 20V MAX system and the FlexVolt system. Both platforms are designed for durability and performance, with most models featuring a bump-feed or automatic feed trimmer head that makes cutting grass and weeds around obstacles fast and efficient. The core design of the trimmer head is nearly identical across both platforms, meaning the process for how to string a Dewalt battery weed eater? is almost the same regardless of which battery system you own. The only minor differences come down to head size, line capacity, and whether the cap requires a tool to remove, which we’ll cover in detail later in this guide.

FlexVolt vs 20V MAX Models

20V MAX weed eaters are ideal for light to medium-duty residential use, with compact, lightweight designs that are easy to maneuver for long periods. They typically use .065″ or .080″ trimmer line, depending on the specific model, and have a twist-off cap for easy access to the spool. FlexVolt weed eaters are built for heavier-duty use, with more powerful motors and larger cutting swaths, making them a better choice for commercial landscapers or homeowners with large, overgrown yards. Most FlexVolt models use .080″ trimmer line, with some heavy-duty variants supporting .095″ line for cutting thick brush and woody vegetation. Both platforms are compatible with Dewalt’s wide range of batteries, so you can use the same battery pack across your entire Dewalt tool collection if you already own other cordless tools from the brand.

Tools and Materials You’ll Need

Restringing your Dewalt weed eater requires only a few basic supplies, most of which you likely already have at home. Having everything ready before you start will make the process faster and more efficient. Here’s what you’ll need:

• Replacement trimmer line: Make sure to purchase line that matches the recommended size for your specific Dewalt model. Most 20V MAX models use .065″ or .080″ line, while most FlexVolt models use .080″ line. Dewalt sells branded pre-cut line spools, but high-quality third-party options work just as well.
• Scissors or trimmer line cutter: A sharp pair of scissors or a dedicated line cutter will give you a clean, even cut to prevent fraying and jams. Many Dewalt weed eaters have a built-in line cutter on the head, so you may not need a separate tool.
• Soft cloth: Use this to wipe away grass, dirt, and debris from the trimmer head before you start working.
• Work gloves: Sharp trimmer line can cut your hands easily, so a pair of basic work gloves will protect you from injury.
• Small flathead screwdriver (optional): Some heavy-duty FlexVolt models have a screw-held cap instead of a twist-off design, so you may need a screwdriver to remove it. This tool is also helpful for prying out stuck old line without damaging the spool.

Safety Precautions Before Starting

Before you begin working on your weed eater, take a few minutes to follow these safety guidelines to avoid injury or damage to your tool:

1. Remove the battery pack first: Never work on your weed eater with the battery installed, as accidental trigger activation can cause the trimmer head to spin unexpectedly and cause serious injury. Remove the battery from the tool and store it in a cool, dry place out of reach of children and pets.
2. Wear protective gear: In addition to work gloves, wear safety glasses if you’re working in a dusty or debris-filled area, and closed-toe shoes to protect your feet from sharp line ends.
3. Work in a well-lit, clear area: Make sure you have plenty of light to see the small components of the trimmer head, and clear away any clutter that could cause you to trip or knock the tool over.
4. Let the tool cool down first: If you just used your weed eater, wait 10 to 15 minutes for the motor and cutting head to cool down before handling them to avoid burns.
5. Don’t force parts: If the cap or spool is stuck, don’t yank or pry it with excessive force, as you can crack the plastic housing. Use a small flathead screwdriver to gently loosen it, or wiggle the cap back and forth to free it.

Step-by-Step Guide to Stringing Your Dewalt Weed Eater

Now that you have your tools and have taken the necessary safety precautions, follow these simple steps to restring your Dewalt battery weed eater. This process works for nearly all 20V MAX and FlexVolt models, with minor adjustments for heavy-duty heads as noted.

Step 1: Prepare the Weeder

Lay your weed eater on a flat, stable surface like a workbench or the ground. Wipe down the trimmer head with your soft cloth to remove any built-up grass, dirt, or debris that could fall into the head when you remove the cap. If your model has a debris shield, remove it first for easier access to the spool. Take a moment to inspect the head for any cracks or damaged components, as a broken head will need to be replaced before you can install new line.

Step 2: Remove Old Trimmer Line

Most Dewalt weed eaters have a twist-off cap that secures the spool inside the head. Turn the cap counterclockwise (left) to loosen it, then pull it straight off to expose the spool. If your model has a screw-held cap, use a small flathead screwdriver to remove the screw, then take off the cap. Pull the old spool out of the head, and remove any remaining pieces of old line from the spool and the head housing. If the old line is stuck to the spool, use your flathead screwdriver to gently pry it off, being careful not to damage the spool’s notches or the feed holes in the head. Discard the old line and spool if it’s damaged, or set the spool aside if it’s still in good condition and you plan to reuse it.

Step 3: Measure and Cut New Line

Take your replacement trimmer line and cut a length that is 1.5 times the length of your old line, which is typically 10 to 18 feet depending on your model. For most 20V MAX models, 10 to 12 feet of .065″ or .080″ line is sufficient, while FlexVolt models usually require 12 to 18 feet of .080″ line. Use your scissors or line cutter to make a clean, straight cut; ragged or frayed ends can cause the line to jam in the feed mechanism or break prematurely. If your line came pre-cut on a spool, you can skip this step and use the full pre-cut length.

Step 4: Load the New Line Into the Head

If you removed the old spool from the head, place the new spool (or the cleaned old spool) back into the head housing, making sure it seats fully into the bottom of the head. Look for an arrow on the side of the spool, which indicates the direction you should wrap the line (almost always clockwise). Insert one end of your cut line into the small hole in the center of the spool, then wrap the line evenly around the spool in the direction of the arrow. Do not overlap the line, as this will cause jams and uneven feeding. As you wrap, make sure the line sits in the notches on the spool to keep it from slipping. Once you’ve wrapped the full length of line, tuck the ends of the line into the small feed holes on either side of the spool, leaving 6 to 8 inches of line sticking out of each hole. This excess line is what will feed out when you bump the head or activate the automatic feed.

Step 5: Reassemble and Test

Place the cap back onto the head, turning it clockwise (right) to tighten it until it clicks or is firmly seated. If your model uses a screw-held cap, insert and tighten the screw until it’s snug, but don’t overtighten, as this can strip the threads. Reinsert the battery pack into the weed eater until it clicks into place. Hold the weed eater with the cutting head facing away from you and any bystanders, then pull the trigger briefly to test the feed. If you have a bump-feed model, tap the head lightly on the ground to see if the line extends automatically. If the line feeds smoothly and extends to the correct length (usually 4 to 6 inches from the head), you’re done. If the line doesn’t feed, double-check that you installed it in the correct direction, that the ends are tucked into the feed holes, and that the spool is seated correctly inside the head.

Comparison of Dewalt Weed Eater Stringing Systems

While the core process for how to string a Dewalt battery weed eater? is nearly identical across all models, there are small differences between the 20V MAX and FlexVolt platforms that may affect your experience. The table below breaks down the key differences to help you understand what to expect when restringing your specific model.

As you can see, the process is very similar across both platforms, with the only real difference being the need for a screwdriver on some heavy-duty FlexVolt models. No matter which model you own, you’ll be able to restring it quickly with this guide.

Tips for Longer Line Life and Easier Stringing

With a few simple best practices, you can extend the life of your trimmer line and make restringing your Dewalt weed eater even faster in the future. These tips are based on feedback from professional landscapers and long-time Dewalt users:

• Keep pre-cut spare line on hand: Store a few pre-cut lengths of the correct trimmer line in your garage or shed so you don’t have to measure and cut new line every time you need to restring. You can even keep a spare loaded spool on hand to swap out in seconds when your line wears down.
• Use high-quality line: Cheap, low-quality trimmer line breaks easily, frays quickly, and can damage the feed mechanism in your weed eater head. Stick to Dewalt branded line or reputable third-party options that are rated for your model’s line size. For areas with thick weeds or woody vegetation, opt for a heavier, reinforced line that resists breaking.
• Wrap line tightly and evenly: When loading the line onto the spool, pull it taut as you wrap to avoid loose layers. Loose line can slip off the spool, cause jams, and feed unevenly, leading to poor cutting performance.
• Clean the head regularly: After each use, wipe down the trimmer head to remove grass clippings, dirt, and debris. Built-up gunk can clog the feed mechanism and make it harder for line to extend properly, even after you restring it.
• Don’t overtighten the cap: When reassembling the head, tighten the cap just until it’s snug. Overtightening can strip the plastic threads on the head or spool, making it impossible to remove later when you need to restring again.

Common Mistakes to Avoid

Even experienced DIYers make mistakes when restringing their weed eaters, leading to jams, poor cutting performance, or even damage to the tool. Avoid these common errors to make the process smoother and extend the life of your weed eater:

1. Using the wrong line size: Using line that’s too thick will prevent it from fitting through the feed holes in the head, while line that’s too thin will break easily and won’t cut thick weeds effectively. Always check your owner’s manual or the label on the side of the head for the exact recommended line size for your model.
2. Overlapping the line when wrapping the spool: Overlapping creates bulky, uneven layers that catch on the head housing and prevent the line from feeding smoothly. Wrap the line in neat, non-overlapping layers, and tuck the ends into the feed holes securely.
3. Skipping battery removal: Working on your weed eater with the battery installed is one of the most dangerous mistakes you can make. Even if you think the trigger is locked, accidental activation can cause the head to spin suddenly and cause serious injury. Always remove the battery before performing any maintenance.
4. Not leaving enough excess line: If you don’t leave 6 to 8 inches of line sticking out of the feed holes on each side of the spool, the line won’t extend when you bump the head or activate the feed. This will leave you with no cutting line mid-job, forcing you to restring again.
5. Forcing the cap back on if it’s misaligned: If the cap doesn’t sit flush on the head when you try to twist it on, don’t force it. Forcing a misaligned cap can strip the plastic threads on the head or spool, making it impossible to remove later. Remove the cap, check that the spool is seated correctly, and that the line ends are tucked in properly, then try again.
6. Letting line wear down completely before replacing: If you wait until the line is completely worn down to the spool, you risk damaging the feed mechanism or having to cut out tangled, stuck line. Replace your line when there’s only 2 to 3 inches left, before it’s fully worn out.

Frequently Asked Questions

Below are answers to the most common questions users have about restringing their Dewalt battery weed eater. If you don’t see your question answered here, refer to your owner’s manual or contact Dewalt customer support for further assistance.

How often should I change the line on my Dewalt weed eater?

Most users need to replace their trimmer line every 2 to 4 weeks of regular use, depending on how much grass, weeds, and debris they’re cutting. If you notice the line breaking frequently, not feeding properly, or failing to cut thick weeds effectively, it’s time to restring. For light residential use (1 to 2 hours per week), you may only need to replace the line once a month, while heavy commercial use may require restringing once a week.

Can I use aftermarket trimmer line in my Dewalt?

Yes, you can use high-quality aftermarket trimmer line that matches the recommended size for your specific model. Avoid cheap, low-quality line, as it breaks easily, wears out faster, and can damage the feed mechanism in your weed eater head. Dewalt branded line is formulated to work seamlessly with their heads, but reputable third-party options from brands like Oregon or ECHO work just as well for most users.

Why won’t my line feed properly after stringing?

The most common causes of feeding issues are: line that’s wrapped too tightly or too loosely on the spool, line that’s too long or too short, the spool not being seated correctly in the head, or a clogged feed mechanism from built-up grass and debris. First, check that the line is installed in the correct direction (matching the arrow on the spool), that the ends are tucked into the feed holes, and that the spool is fully seated in the head. If the feed mechanism is clogged, clean it out with a soft cloth and a small amount of rubbing alcohol.

Do I need to remove the battery before stringing?

Absolutely. Never work on your weed eater with the battery installed, as accidental trigger activation can cause the trimmer head to spin unexpectedly and cause serious injury. Always remove the battery and store it in a safe, dry place out of reach of children and pets before performing any maintenance, including restringing.

What size trimmer line does my Dewalt use?

Most 20V MAX Dewalt weed eaters use either .065″ (light-duty models) or .080″ (standard models) trimmer line, while most FlexVolt models use .080″ line, with some heavy-duty commercial variants supporting .095″ line for cutting thick brush. The easiest way to find the exact size for your model is to check the label on the side of the trimmer head or refer to your owner’s manual. If you’re still unsure, you can remove the old line and measure its diameter with a set of calipers to get the exact size.

Conclusion

Learning how to string a Dewalt battery weed eater? is a simple, valuable skill that will save you time and money on professional maintenance while keeping your yard looking neat and well-maintained. Whether you own a lightweight 20V MAX model for residential use or a heavy-duty FlexVolt model for larger properties, the restringing process is straightforward and requires only basic tools and a few minutes of your time. By following the step-by-step guide in this article, avoiding common mistakes, and implementing the tips for longer line life, you can keep your Dewalt weed eater running smoothly for years to come. Remember to always prioritize safety by removing the battery before performing any maintenance, use the correct trimmer line size for your model, and wrap the line evenly around the spool to avoid jams. With this guide, you’ll never have to struggle with a worn-out trimmer line again, and you can get back to tackling your yard work with ease.