Sharpening chainsaw chains: It works with these battery-powered devices.

Sharpening and Grinding Chainsaw Chains

There are various tools available for filing and grinding chainsaw chains. Many of them do not really simplify the work. What can the battery-operated sharpeners "Schleiferl light" and "KSX chain sharpener" do?

This article first appeared in the "Wochenblatt for Agriculture and Rural Life."

Sharpening a chainsaw with a round file is a challenge for occasional users. The alternative - the chain grinding service - is sometimes not ideal: in addition to the costs, more material is often removed during grinding than necessary, or the teeth become too hot. This results in a significantly shorter lifespan for the chain compared to self-sharpened ones.

BaSt-Ing and Forstreich offer two mobile, battery-powered chain sharpeners with their "Schleiferl light" and "KSX chain sharpener." These tools are designed for amateurs to handle easily. However, professionals are also targeted by the providers.

Grinding and Milling

BaSt-Ing and Forstreich have two different approaches with their sharpening tools. They grind or mill the chain teeth. This allows for more material removal in the same amount of time compared to filing. However, there is a risk of overheating the material and losing hardness. After using both devices for an extended period, we found that while they require some practice, they can achieve good results. None of our teeth were burnt out.

Together with the Schleiferl, BaSt-Ing offers a depth limiter tool. It ensures that the depth limiters are precisely adjusted to the height of each tooth. The goal is for each tooth to remove the same chip thickness and for the resistance to be the same on all teeth, regardless of the remaining length of the tooth top. This ensures that the chain runs straight even with teeth of different lengths, eliminating the need to grind back to the shortest tooth. We tested this with a corresponding chain. Even though the length difference between the longest and shortest tooth top was 3 mm and the teeth were very unevenly ground, the chain ran straight. A similar filing guide is also available with the FL 4 model from Stihl, although we have not tested whether it achieves the same effect.

Affordable "Light Version"

BaSt-Ing has been offering the Schleiferl in the professional version made of aluminum for several years. However, the price of around 340€ scares off occasional users. Therefore, the company introduced the "Schleiferl light" version for around 200€ last year. The device operates on the same principle as its larger counterpart but is entirely made of plastic.

The Schleiferl light is handheld and designed for sharpening the chain on the bar. For the drive, it is best to use a cordless impact wrench on the hexagonal attachment - more on that later. It drives a spring-loaded grinding belt that runs over the so-called grinding shaft at the lower end. This shaft is interchangeable and available in various diameters, making the Schleiferl suitable for all chain pitch sizes. Bilateral angle indicators set the cutting and sharpening angles.

Correct Speed is Essential

The all-plastic design of the Schleiferl light may give a somewhat simple impression. Especially when using a standard cordless screwdriver for the drive, it rattles noticeably. This is due to the low speed. Simple screwdrivers often do not even reach 2000 rpm. This is insufficient for a decent grinding result. Manufacturer BaSt-Ing recommends a light impact wrench with at least 3000 rpm for a reason. The machine runs smoother, and work is easier. A low speed can lead to applying more pressure on the grinding belt to achieve more material removal. However, this can cause the belt to stop or jam sideways, leading to more wear and tear.

At 3000 rpm, precise grinding with little pressure is possible. The correct position is crucial. If the bar is clamped too high, it does not work smoothly, and the view of the tooth is obstructed.

With the bilateral angle indicators, left and right teeth can be ground without turning the saw. If you want to grind other angles than the preset 30°, you can do so. The indicators provide enough flexibility. It is essential that they are parallel to the bar to ensure the correct sharpening angle.

Depending on how intensively the chains are worked on, a grinding belt lasts until the teeth of a chain are ground down. The replacement is quick. Unlock the lever for the spring preload, loosen four screws on the cover, and change the grinding belt. A replacement belt costs 5.95€.

Working with the Schleiferl light takes some getting used to. However, using a cordless impact wrench in the left hand and the Schleiferl in the right hand works quickly. Unfortunately, the appearance of the device is somewhat simple and does not quite justify the price. However, the work results are very good. For less tech-savvy users, we would appreciate a brief user manual.

Handy "KSX"

The basis for the "Forstreich KSX" chain sharpener is a 12V straight grinder from Milwaukee. For use as a chain sharpener, Forstreich has combined it with an angle and height stop. It provides a sharpening angle of 30° and ensures the correct top and side plate angles. Other sharpening angles are possible by slightly tilting the grinder, although this lacks the precise stop. An optional 10° angle stop is also available. The sharpener costs 299€ without a charger, including a 4Ah battery and two milling bits. The charger adds another approximately 75€. If you already own a 12V straight grinder from Milwaukee, you can order the angle stop separately for 38€.

The sharpening pin, according to Forstreich, is a proprietary development designed to ensure long service life and maintain the diameter throughout its use. Different pin diameters are available for various chain pitches for around 30€ each.

The KSX weighs around 1 kg, is well-balanced, and therefore very handy. Working with the grinder is easy. The design of the angle stop is advantageous for quick work. Sharpening the left and right teeth can be done from one side, without the need to rotate the saw or change the operator's position.

Although the Milwaukee straight grinder offers three speed settings, we found the first one to be the best. This setting minimizes the risk of removing too much material or overheating the tooth. With some practice, you quickly learn how much pressure is needed for the right result. Then, a pin can last up to six chains.

At around 380€ for the complete set with battery, charger, straight grinder, and two sharpening pins, this price is something occasional users should consider carefully. Compared to the Schleiferl light, the handling is much easier. Both devices allow for quick grinding/milling. Sharp teeth are guaranteed.

Calculate Individually

Whether the purchase of one of these sharpeners is worthwhile is something each individual needs to calculate. Factors such as more efficient work with sharp chains, time saved on sharpening, or material preservation should also be considered.

Sharpening chains as a service costs between 6 and 8€. If more material is removed than necessary, self-sharpened chains have a longer lifespan, which is also a significant factor to consider. Additionally, there is the cost of purchasing the sharpeners, sharpening pins, or grinding belts. Sometimes, it is better to have them and not need them.

Our Recommendation

For those looking for a simple manual method for chain sharpening, we recommend the "Chain Sharp CS-X" sharpener from Pferd (also available in Stihl colors). It combines filing the tooth and depth limiter in one step. The application is straightforward, with pictograms on the handles showing how to correctly use the file combination. With some practice, good results can be achieved. A separate Chain Sharp CS-X is required for each chain pitch, meaning if you use a 325 chain, you need to purchase the device designed for it with a 4.8mm file diameter. Depending on the provider, the price ranges between 40 and 45€.

Avoid

For 16 to 25€ (depending on the provider), this "file tool" from the depths of the internet is no bargain. The work results are more than mediocre, and the handling involves some fumbling. The conical files at the end of the crank are supposed to be suitable for various chain pitches. However, the user cannot see at which point the file section has which diameter. Furthermore, only moderate material removal is achieved by cranking. Three crank files are included. When they wear out, the device will likely end up in the corner, as the secret of where to get suitable replacement files remains unknown.

This article was first published in April 2024 on topagrar.com. Due to ongoing reader interest, we have republished it. Your top agrar editorial team.