Pruning, felling, firewood for the barbecue, stove and fireplace… So much work that will always see our faithful chainsaw (sometimes even mistreated or insulted). All models, from the professional to the cheaper, from the powerful chainsaw with internal combustion engine to the light and vispo tool for pruning, always have one thing in common: the cutting chain.
And it is precisely the chainsaw chain that we will talk about in this article because its perfect sharpening determines the quality of work and the performance of the machine. The sharpening quality of chainsaws is often underestimated, especially among amateurs and non-professional users, so it is good to take care of this operation and always work with a high-performance chain. We could also have in our hands the top model of a big brand, but if the chain is not in good condition, we will continue to work badly, with more effort, more slowly and indirectly exposing ourselves. at greater risk.
Below we will see schematically how to understand when it is time to sharpen, what tools are needed to do it and how to carry it out efficiently, without resorting to the services of a mechanic.
Understand when the chain needs to be sharpened
What tools are needed for sharpening
prepare the chain
How to sharpen
Useful accessories for better sharpening
Know when to sharpen the chain
Our chainsaw works by moving a toothed chain, which slides on the rails of a bar and cuts the wood, on the principle of a miniature planer. To limit the depth of cut, each tooth is preceded by a blunt fin, called depth limiter.
Three factors are necessary to ensure that the cut is carried out cleanly, without straining the motor and without overheating the cutting equipment:
Good lubrication of the cutting device.
Correct chain tension
Good gnashing of teeth.
For the first two factors, I recommend reading the article on chainsaw maintenance, which will tell you how to ensure proper chain lubrication and how to adjust the chain tension. However, for the exacerbation, it is essential to be able to recognize the right time to intervene.
In fact, to avoid uneven tooth wear or damage to the chain and bar, it would be good to use light but more frequent sharpening. The signals that make it possible to recognize a chain to be sharpened are these factors:
- dusty chip . The chip produced has become thinner and/or a lot of dust is produced when cutting.
- A hard cut. The saw needs pressure on the handles to advance the cut.
- Increase in smoking. Although the lubrication is perfect, some smoke can be perceived during long cuts.
- gaps when cutting . The cut tends to drift to one side.
These factors can obviously occur at different frequencies and intensities, depending on the hand of the operator using the chainsaw, the essence of the cut, the type of chainsaw and the chain mounted.
For these reasons, I recommend that you continue to give a light stroke of the file every three solids made to revive the razor’s edge and continue to function satisfactorily until it’s time for a thorough checkup and possibly an artistic restoration.
What tools do you need for sharpening
Good sharpening requires a minimum of manual dexterity, the right technique and the right tools.
To proceed with the sharpening we will need to block the saw bar in a stable way, then a vice or those fixed on a stump if you are in the forest and want to do the work directly.
Then you need the real sharpening tools: a round file of the right diameter for the chain mounted, a template also specific to the chain used, and a felt. Perhaps an indicator, if the chain has very irregular teeth between them.
To fully understand which file you need, consult the mounted chain pitch, which you must know when buying your chainsaw but which is always printed on the links of the chain (on the depth gauge or on the wing that slides on the guide). For example, STIHL has a number from 1 to 5 on the depth gauge for easy selection, and each has a chain pitch and then a file.
One thing you never do is take your gloves off to better handle the tools. Instead, bring a second pair of thinner, mechanic-like gloves to wear when sharpening: the chain’s grooved teeth seem ineffective on wood, but are still sharp enough to bruise skin and flesh if, inadvertently, he ends up slipping his hand over it.
We will now go into the details of the work to be done, with some useful tips on how to sharpen a chain. Obviously, getting the job done right requires practical skills that can only be acquired through practice, but a little theory can go a long way towards setting up the operation correctly.
prepare the chain
First, the chain is cleaned of the remains of wood, resin and sawdust mixed with chain oil, in order to check its integrity and state of wear.
If in a first analysis there are no anomalies and the teeth all seem uniformly worn, you can choose to mark one of them with a marker to choose it as a reference.
If on the other hand the teeth are very different from each other, it is good to use a gauge to check which is the most worn and mark the latter as a reference, all the other teeth must be reduced to the same size that this tooth will assume once sharpened.
How to sharpen
We are ready to start sharpening the teeth: at this point the chain is stretched more than it is during work and the bar is fixed in the vice, to be able to work comfortably, without ending the chain unstable while trying to sharpen it
When sharpening a chain, the teeth with the same side edge are worked first (for example, the one on the left, looking at the chain from above), then all those with the opposite side edge (then the right). Indeed, the file must be used with movements from the inside to the outside of the tooth and therefore it would be inconvenient to continually change position, it would be better to hold it along the chain and then rotate the saw on the other side. .or move physically.
At this point, we can begin the actual act of sharpening by following these points:
It sharpens with fluid movements from the inside to the outside of the cutting edge, without the need for pressure.
Turn the file over occasionally so that it wears evenly.
The file should move perpendicular to the bar, imagine that a 90° angle should be maintained between the file handle and the bar.
Unless otherwise specified, the sharpening angle of the teeth should be maintained at 30°.
Do not push the file into the bottom of the dent seat, keep it slightly elevated so that it protrudes about ¼ of its diameter above the dent: the cutting part that works is the outermost part of the mesh, not the internal part!
Once you’ve sharpened all the teeth, place the jig on one of them and file the protruding part of the depth gauge with the flat file.
A tip to know if it is working properly is to color the edge of the teeth with the marker and see if the metal removal is uniform, this can be useful as a feedback and to get familiar with the correct reasons.
To make your life easier or speed up sharpening operations, there are many tools on the market, some of which consist of a bridge with two rollers that stabilize the file when moving, preventing it from losing the 90° angle. (gate guide). Others incorporate strikers on the handle of the file holder that allow the file to be placed at the correct height in relation to the tooth, others even implement the flat file for the limiter, to adjust it and sharpen the cutting in a single gesture.