Chainsaw bars are made from some of the highest quality steel on the market, designed to slice through thick obstacles in high volumes without ever cracking and breaking. With such a durable construction, it should last a lifetime, right? You might want to think again, as even the sturdiest of chainsaw bars may need to be replaced after significant use.
When is it time to replace a chainsaw’s bar? A chainsaw’s bar should be replaced any time you notice any visible signs of wear. Specifically, the formation of a burr, or a fold-like deformation on the bar’s cutting edge, is a classic indication that a replacement is necessary.
In addition to burrs, several other indicators can let you know that the bar needs to be replaced. It is essential not to try to continue to use your chainsaw with a damaged bar, as this can lead to the slipping or breaking of your chain, which would put your physical safety at risk once the chain comes off the bar.
Signs That a Chainsaw’s Bar Needs to Be Replaced
A chainsaw’s bar is durable but not indestructible. After significant wear and tear, it needs to be replaced.
The physical signs that a chainsaw’s bar should be replaced are fairly easy to identify, but may not always be visible at first glance. In many cases, you may not be able to notice them if the chain is still on the bar. As such, it is recommended to remove the chain to give the bar’s condition a thorough examination.
The following indicators may be present or in combination with one another to let you know that a replacement bar is necessary. Additionally, you can check out this video below, as it does a really good job explaining what to look for.
Formation of Burrs
A burr is a deformation that occurs on fine metal edges due to heavy use or abuse. On your chainsaw’s bar, it may manifest itself in the form of a small indentation in which the sides of the metal bar, which should be straight, fold over the sides to create a little mushroom-like effect at the top of the bar.
Most chainsaws will be able to continue functioning with small burrs, so they will not be noticeable unless the chain is removed. However, the deeper the burrs become, the more likely it is that the chain will catch or slip off the bar, causing a potential catastrophe.
Burrs form due to extreme heat and repeated pressure when the bar’s metal is hot and slightly more malleable. Therefore, you must keep your chain properly oiled to reduce heat-inducing friction on the blade and avoid pressing down on the exact same spot when making cuts to prevent concentrating the pressure at one burr-causing location.
A good chainsaw bar should be completely smooth. Similar to how burrs are formed, heat and overuse can cause peeling and abrasion that lead to the formation of small splinters near the bar’s edge. In addition, poorly cleaned bars and the buildup of debris can expedite and/or instigate the splintering of your chainsaw’s bar.
Chainsaw bars that are heavily splintered can cause grinding that leads to the worsening of the condition, not to mention the possibility of the chain catching during use, ceasing and potentially breaking the chain, putting undue stress on the saw’s engine.
Burning is caused due to too much friction, caused by an improperly oiled chain or repeated attempts to saw through materials that are too tough for a specific saw. Burning is characterized by heavy black smudging on the bar’s surface.
While the black smudging may simply be a stain from a wood’s pitch or resin and no serious cause for concern, all smudges should be thoroughly examined. If you can run your fingers across the face of the bar and feel any dips or indentations, then you can be sure that the high heat has burned your bar and could put its integrity for future use at risk.
Another sign to look for is the presence of a bent or warped bar. If you can hold the bar and notice it curving or bending in either direction, it is time for a replacement. Warping is likely due to excessive force, although high temperatures are always a possibility.
Many chainsaw bars are painted with the brand or decal of the manufacturer. While this paint will eventually fade, peel, and become discolored, even in perfectly healthy bars, you can be assured that areas of the bar that still have the paint are in good condition.
Therefore, when looking at your chainsaw’s bar, spend extra time looking at the areas where the paint has faded, as these will be the first indication of any damage—if there is any damage at all.
Poorly Fitting Chain
A good chain should fit snugly on the bar. When pulling on the chain, it should give enough to where there is some light between the bar and chain and then snap soundly back in place when released. This snug fit should be maintained around the periphery of the chainsaw’s bar.
While chains sag most likely because of a chain that is improperly installed or worn out, there is a chance that the chain is not fitting correctly due to the bar shrinking or becoming deformed to the point that even new chains cannot fit securely. Test a couple of chains that you know to be in good condition to help you confirm or reject the bar as the culprit.
Some chainsaws, especially those gas-powered versions, can be loud, making it hard to hear anything other than the roar of the engine in action. However, if you can detect any grinding or clicking that is not typical of a smoothly operating chainsaw, it could be the indication of a degraded bar.
Catching of the Sprocket
On the inside of the chainsaw bar is the sprocket around which the chain rotates, similar to how the chain on a bike goes around sprockets to propel it forward.
With the chainsaw off and the chain removed, try rotating this sprocket gently with your fingers. If it does not turn freely, the bar is damaged and needs to be replaced.
How to Lengthen the Life of Your Chainsaw’s Bar
Although they are fabricated from the highest quality steel, chainsaw bars will eventually need to be replaced after extensive use. However, the following tips can be used to maximize the life of your bar and minimize the likelihood you will need a replacement.
Chainsaw ownership teaches you to keep your chain properly oiled. However, this can be difficult to keep up with in times of heavy use.
Not only does oiling keep your chain from rusting, cracking, and breaking, but it reduces the friction that causes heat, the primary cause of burrs, burns, splintering, and warping on your bar.
Even with a properly oiled chain and bar, some friction will occur, causing your blade to get very hot. Therefore, to prevent the heat from building up to a level that can lead to temperatures that will degrade the bar, give your chainsaw some small breaks every few minutes to allow the bar to cool.
Do Not Force Any Cuts
Using a chainsaw can make you feel invincible. While it definitely makes cuts that would otherwise take you hours with an ax and two strong arms, it cannot do everything.
With that said, my final tip is this: If you ever notice your chainsaw hitting anything hard, beginning to smoke, or having any difficulty continuing its path, stop the cut before you bend the bar and damage your chainsaw.