A smooth functioning chainsaw cuts through wood like butter and makes quick work out of any pile of wood. Right up until things go sideways. And I mean that literally. One day your saw cuts perfectly straight and the next time it starts cutting crooked. A crooked cut might not seem like a big deal if you’re chunking up firewood. But it does get frustrating once the saw starts binding up, jerking in your hand or even tries to kick back on you.
So what’s the deal? Why is your saw starting to cut crooked? And more importantly, how do you solve the problem?
Nine times out of ten, a crooked cut is caused by a problem with your chainsaw’s chain such as dull or damaged cutting teeth, irregular cutter size or worn depth gauges in need of adjustment. Less common causes include a misaligned dawg bolt that dulls the chain on one side or a bent bar.
Diagnosing the true problem is a matter of simple deduction that always starts with inspecting your chain. Not everyone knows what to look for, let alone how fix an issue with a chain, so keep reading and we’ll figure it out together.
Top 3 causes of crooked cuts
Chainsaw chains are more complex than you might think at first glance. There are a lot of critical parts that cause major issues with the slightest imbalance. If you’re wondering how you’ll even notice a problem, trust me, you will. In addition to crooked cuts, your saw might grab and jerk in your hand, it may cut super slow or you get a dangerous kick back just as you start cutting.
These are all signs that something is wrong. Stop cutting and take a look at your chain. Let’s go over the 3 most common chain defects that lead to crooked cuts and how to spot them.
1. Dull or damaged teeth
Symptoms:
After enough use and abuse, your chain is bound to have a few teeth with major nicks, dulled cutting corners or damaged top plates. One of the first symptoms you’ll notice is a slower and rougher cut. You may also experience slanting cuts if there are more damaged teeth on one side compared to the other.
Causes:
The primary cause of dulled or damaged teeth is dirty cutting conditions. Let’s face it, most of the wood you cut isn’t pristinely clean. Dirt or rocks that work their way into the path of your saw don’t cut like wood. Get enough debris slamming into the chain at high speed and there’s going to be damage. Another cause, though less common, is overheating. If you run your saw out of bar oil, increased friction heats up and softens the steel chain, resulting in faster wear on the cutters.
How to spot it:
With the saw turned off, check for damage or dulling by inspecting each of the cutters on the chain. The top plate, side plate and the cutting corner on every tooth (or cutter) should have a clean, sharp bevel free of nicks. Any teeth that have flattened bevels or have an off-skew cutting angle when compared to other teeth are in need of repair.
How to fix it:
How you go about fixing a dull chainsaw chain depends on the severity of the damage. A few rounded bevels on the cutters or some minor rock nicks can be sorted out by manually sharpening the offending teeth with a hand file. Depending on your sharpening skills, most moderate damage to the cutting teeth on a chain are also fixable using proper sharpening techniques. More severe damage, on the other hand, may require expert sharpening. With extreme cases, such as completely missing teeth, it’s better to purchase a new chain all together.
Prevention:
If you find that your chain is in constant need of sharpening, it’s time to asses what you might be doing wrong. You can drastically prolong the life of your chain and avoid rough or crooked cuts by keeping your chainsaw off the ground when cutting. You should also avoid cutting wood that has copious amounts of dirt and debris imbedded in the bark. At the very least, use a small hand brush to sweep most of the debris off before cutting.
2. Irregular cutter size or angle
Symptoms:
Unlike the problem we just talked about, irregular cutter size or angles manifest itself mostly in the the form of crooked cuts. The slant and speed of your cut may not always be noticeable until the problem gets worse. Eventually though, your cuts will be so crooked that the chainsaw will bind up or get stuck as you try lifting it out from the cut line.
Causes:
Inconsistencies in the size of the cutting teeth, as well as variations in the cutter angles, is almost always caused by poor sharpening techniques. It’s also a compounding issue for chainsaw owners that frequently dull their chains. They manually sharpen more often but do it incorrectly and the result is uneven teeth that cut more aggressively on one side. Sharpening a chain isn’t rocket science but because most of us have a dominant hand, it means teeth facing one direction on the chain tend to get sharpened differently than on the other side of the chain. Sloppy sharpening also leads to inconsistent angles on the cutter or an over sharpening of the gullet rather than the top plate on the cutter.
How to spot it:
It’s relatively easy to spot a poorly sharpened chain. Again, with the saw turned off, take a look at every tooth on the chain. If the teeth all facing the same direction are smaller than teeth on the other side then you found the cause of your crooked cuts. When a saw pulls to the left as it cuts, it means the cutters on the right side of the chain are taking a bigger bite and visa versa. When the slant of your cut is just starting to be noticeable, try using a caliper to compare the size of each cutter. Inconsistent sharpening angles are tougher to spot. Look straight down on the chain and try to gauge if all the top plates have the same angle.
How to fix it:
Don’t beat yourself up. It takes practice to get good at sharpening a chain. I’m hardly a master at it. But take solace in knowing that it is possible to fix a poorly sharpened chain. Take a little time to brush up on your sharpening techniques and invest in the right tools for the job. Hand sharpening with a round file takes practice. Consider getting a sharpening jig to help you maintain the correct angle on opposing teeth. Either way, you’ll need to file down larger cutters to match the size of the smallest cutter on the chain. That way, they all take the same size bite out of the wood for a straight cut. Check your progress with an accurate caliper.
Prevention:
It’s hard but once you finally admit that your sharpening prowess is not up to snuff, just start practicing. Watch a few Youtube videos on the subject and get the right techniques dialed in. Practice sharpening the opposing cutters evenly with both your dominant and non-dominant hand. Keep an eye on your sharpening angle as well. Most newer chains have an etched line on the top plate that indicates the appropriate angle. Try matching it as closely as possible.
3. Worn depth gauges
Symptoms:
The depth gauges (aka. rakers) on a chain don’t get nearly enough attention from chainsaw operators. Neglected depth gauges can wreak havoc on the quality of your cut and most of us immediately assume something must be wrong with the cutters. However, it’s possible to tell when your rakers are excessively worn. The most apparent symptom is a saw that jumps up and down or jerks forward in your hands since the worn depth gauge permits the accompanying cutter to get a bigger bite of wood than it should. Conversely, a depth gauge left too tall will slow down your cuts. You may think it’s because of dull teeth but don’t overlook the rakers. When several depth gauges are either too tall or worn down on links with teeth facing the same direction, you’ll also get a crooked cut.
Causes:
Cutting through debris covered wood or digging your saw into the ground is a likely cause for worn depth gauges. Depth gauges that are riding too high above the cutter result when the cutter wears faster than the depth gauge. Or more likely, the cutter gets sharpened constantly without adjusting the rakers height. Another common issue affecting the depth gauge is someone filing depth gauges without the aid of a depth gauge tool or over filing in an attempt to make the saw cut more aggressively.
How to spot it:
Improperly leveled rakers are tough to spot by eye without experience. The most concise way to see if worn depth gauges are the problem is to use a depth gauge tool. It is a simple tool designed to sit level on the cutters and allow a raker to sit within an exposed grove on the tool.
How to fix it:
First, you need to know what the proper depth gauge height for your chain should be. Find it on the box your chain came in or some chains have it stamped on the side of the cutter tooth. Then, you want to get the corresponding depth gauge tool. Check all your rakers with the tool and see if some are too low or sticking above the measuring tool. For a chain with low depth gauges, it’s best practice to just get a new chain since low depth gauges can result in extremely dangerous kickbacks. If your rakers are sitting a little high, use a flat file to drop them to the right height. It’s always better to remove too little than too much on the rakers.
Prevention:
First, avoid damage to your depth gauges by keeping the chainsaw out of dirt and debris. More importantly, always adjust your rakers to the specified level using a depth gauge tool. Remember, do not over file the depth gauges. Low depth gauges are extremely dangerous. It makes for a rough cut that overworks your saw and increases the risk of kickbacks.
What about a bent or worn out bar
Diagnosing problems on a chain are fairly straight forward. Occasionally though, the problem goes beyond the chain and you may have an issue with the bar. Keep in mind that a bad bar can be hard to spot, so be sure that you’ve ruled out problems with the chain before you jump the gun and assume the bar is to blame.
If you think the bar is causing crooked cuts, it is most likely due to a twist or bend in the bar. Maybe you stepped on it, dropped it or torqued it too hard during a cut. Either way, inspect it closely for a bend or twist by taking it off the saw and laying it on a perfectly flat surface. Any misalignment will be obvious. Be aware that replacing the bar might not fix the issue if there is also a problem with your chain.
When you truly narrow down the crooked cuts to the bar but it isn’t twisted, it is likely worn out rails or worn out grooves on the inside of the bar. There is no way to fix a worn out bar. You’ll need to shell out some cash for a new one.
Other reasons why my chainsaw cuts crooked
As we get further down the list of possible causes for crooked cuts, it gets much harder to be certain of the issue. When all other causes are ruled out, it’s time to take a look at other components of the saw. Check to see if there are any parts near or around the bar and chain that look out of alignment.
There have been instances of dawg bolts that stick out too close to the chain and nick the teeth as they cycle past while cutting. Even after a new chain is installed, the saw eventually pulls to one side as the teeth on the other side start to dull. However, this is an unlikely issue for most.
Final thoughts
At some point, you’ll need to decide when your saw is better off in the hands of an expert. The best course of action may be to let a pro look it over and see what is going on. Ask them if they see any issues with the chain you might have missed before urging them to start replacing parts unnecessarily.
The thing to remember is that more often than not, the chain is your number one suspect on a saw that cuts crooked. Start there and you should be able to solve your own problem.
