Are Weed Eater Heads Universal?

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Weed eater heads are built for heavy duty use. Not surprising given the punishment it takes when you use it to clear weeds and other stuff in the yard. However, these will wear out eventually. If that weed eater or string trimmer head is not working as it used to, it is time to get a new one. And I will show how to find the right trimmer head so let’s get to it.

Most trimmer heads have adapters so you can use it with any weed eater. You can also buy from the manufacturer to ensure the head is 100% compatible.

Are String Trimmer Heads Interchangeable?

Whether you call them weed eater, weed wacker or string trimmer, the heads are universal. As long as you have modern trimmer, finding a compatible head is no problem.

Manufacturers may use different designs for weed eater heads, but that is not going to be an issue. Almost all heads sold are equipped with adapters so you can connect it to any trimmer.

Suppose you want to replace the trimmer head. What are your options?

You can buy from the manufacturer. If you have a Troy-bilt weed eater, you can purchase a replacement head from the company. Because it is from the same brand, it’s guaranteed the head and trimmer are compatible.

But you can also buy from third party suppliers as long as it is compatible with your trimmer. You can get a head exactly like the one you want to replace, or upgrade it. What is important is you do not have to put up with what you got out of the box.

Trimmer heads are replaced for two reasons: either the head is broken or lacks power. Either way you can find one that suits your needs.

What to Look For in a Weed Eater Head

Aside from an adapter, there are other things you have to factor in. Buying a weed eater head is easy, but there is more to it than just an adapter.

Yes, an adapter is needed for universal compatibility, but there are other things that separate one trimmer head from another. And that is what I will explain below.

String Capacity

Aside from the head, you also have to make sure the weed eater string size is correct. To put it another way, the trimmer head capacity determines what string size you can use.

Majority of weed eater heads support 0.065-0.095 inch string sizes. Other models can handle up to 0.105 or greater. Refer to your owner’s manual for the string size capacity.

The thicker the string diameter, the less likely it is to break. This also means greater cutting power. But a thick string requires a more robust trimmer head and engine.

You should only use a string size that the trimmer head can handle. If the string is too thick it can damage the head and worse, the engine. The bottom line is that aside from a compatible trimmer head, the string size must always be considered.


Electric weed eaters work best with a lightweight trimmer head. A heavy head might put a lot of strain on an electric motor. The larger the head, the more resources needed to run it. This can shorten the lifespan of the motor and cause overheating.

Gas powered weed eaters are more capable of handling large heads. In general, gas weed eaters such as the Wild Badger Weed Eater have more powerful engines than electric models..

I know that it’s tempting to get a large heavy duty head. Given the way weed eaters work, we all want a head that can take a lot of hits. But a large head is going to take its toll on the motor, so choose one that is similar in size to the one the trimmer has.

Brush, Blade or String

Some weed eaters have blades or wire brushes instead of strings. Which you choose depends on your personal preference.

Strings or lines are the most popular because of their versatility. But if you have a powerful gas weed eater, consider using a wire brush instead. These are suitable for weeding around your driveway.

Blades are available in metal and plastic varieties. Plastic blades are more popular because there is little risk of it cutting plants and other garden features. Metal blades, while durable, can cause damage.

String Feed Mechanism

Weed eaters use a string to cut weed and other materials. When the string breaks, the trimmer head releases more string. This is known as line feeding and there are different types available.

Fixed. These heads often have blades rather than strings. Others do have strings but manual replacement is needed.

Bump. Bump heads are very common. As the name suggests, you bump the head to make the string come out. It is probably the most popular trimmer head type and works great. However, it is the constant bumping that causes it to wear out.

Automatic. The string automatically comes out. You don’t need to do anything. This works for a lot of people, though the output you get is decided by the mechanism.

The string mechanism you can use might be limited by the weed eater. Check if the system supports different types. If it does, you decide which one suits you best.

Electric and. Gas Trimmer Head Compatibility

Gas and electric weed trimmer heads are usually not compatible. Most heads for gas powered models are fastened by screws, where electric trimmer heads are mostly latch-on.

As someone who has used a lot of electric string trimmers, I can tell you that most heads are proprietary. This is why they are not universal. In contrast, most gas powered models use the same basic design.

Bottom line: most corded weed eaters are only compatible with the head they came with. If you have to replace it, you have to buy from the manufacturer.

If it sounds like electric string trimmer heads are harder to replace than gas, it is. Electric weed eaters tend to be more complex. Most of the parts are also proprietary, so what works for Brand A may not work for Brand B.

Frequently Asked Questions

How often should I replace a weed trimmer head?

When it no longer runs like before. There is no set date or frequency here. If the head no longer works as it did or has suffered damage, get a replacement. Never use a damaged trimmer head as it could wreck the engine.

This is applicable for electric and gas weed eaters. If the string doesn’t come out or the head has some physical damage, get a new one. Even the most durable trimmer head is going to require a replacement at some point.

Is it better to buy a trimmer head from the manufacturer or third party supplier?

If you want to be 100% sure, buy from the manufacturer. But as long as there is an adapter, any trimmer head should work. It depends on your preference. Usually a third party trimmer head manufacturer lists the brands it is compatible with. If your weed eater is a popular brand,

How many trimmer head adapters do I need?

If you only have one string trimmer and use just one head type, a single adapter is fine. But if you use multiple straight shaft string trimmers, look for heads that ship with several adapters.

Are blades better than strings for weed eaters?

Not necessarily. Blades have their uses as do strings. If you want to use blades, look for plastic ones as metal might damage plants nearby. You should also look for blades with several adapters in case you want to try other brands.

Do trimmer heads work the same way?

No. The mechanism for releasing strings or blades differs. You have to check the instructions that come with the trimmer head kit.