Chainsaw cutting crooked? Causes and fixes

Nothing’s more aggravating than gearing up to trim logs with your chainsaw, only to find the blade wandering off course. You crave precision, so it’s downright puzzling when your saw won’t give you that clean, straight cut.

The advice in this article might not align perfectly with your specific chainsaw model. While we aim to offer helpful tips for all sorts of DIY chainsaw repairs, variations in models and setups can lead to differences in troubleshooting steps, part replacements, and so on. For the most accurate guidance, we strongly recommend checking the manufacturer documentation for your specific chainsaw model or reach out to us with any questions.

Why a chainsaw cuts crooked

When your chainsaw starts cutting crooked, something’s usually off-balance or worn out. You might suspect issues like a dull chain, a misaligned bar, uneven chain teeth, or even user technique. Any of these can affect how smoothly and accurately the chain slices through the wood. If any part is bent, damaged, or improperly adjusted, your saw’s cutting path can tilt to one side. The good news? With a bit of know-how and the right approach, you can sort out most of these problems right in your workshop.

Get ready for safe troubleshooting

Before diving into any inspection or repair, safety first. Always switch off your chainsaw and disconnect the spark plug cable to eliminate any chance of accidental starts. Wear sturdy gloves to protect your hands from slips, and safety glasses to shield your eyes from debris. It’s also a good idea to place your chainsaw on a solid, flat surface to give yourself stability when making adjustments. If you need extra safety tips, check the manual that came with your chainsaw. For more repair help, swing by our repair help resources anytime.

Fix user technique

Sometimes, it’s not the machine but the way you’re handling it. If you apply uneven pressure, push the bar at an angle, or force the saw through wood too aggressively, you can end up with a crooked cut. The upside is that a slight tweak to your stance or cutting method might instantly improve cut quality.

Hold the saw properly

Keep a firm grip with both hands, thumbs wrapped around the handles. Stand with your feet about shoulder-width apart for stability, and align the blade so it’s perpendicular to the log or whatever you’re cutting. Try letting the chainsaw do the work instead of forcing it with all your might.

Manage cutting pressure

1. Let the sharp chain cutters bite into the wood naturally.
2. Apply only light to moderate pressure. Pushing too hard can make the chain bind and veer off course.
3. Keep the bar straight and steady as you cut, allowing the chain to follow its natural path.

Fine-tuning your technique often clears up minor crookedness, especially if you’ve already checked that the bar, chain, and tension are in good shape.

Double-check chain tension and lubrication

A chain that’s not properly tensioned can pull your saw to one side. If it’s too tight, it can bind and drift; too loose, and it can flop around the bar, leading to crooked cuts. You also need good lubrication so the chain glides smoothly, reducing wear on the bar and chain.

How to check tension

1. With protective gloves on and the chainsaw off, pull the chain up from the top of the bar. You should see about half of the bar groove but no more.
2. Try spinning the chain by hand. It should move freely without sagging below the bar.
3. Check your chainsaw manual for the recommended chain tension. Make small adjustments using the tensioning screw near the guide bar until it feels just right.

Ensure proper chain oiling

1. Keep an eye on the oil reservoir. Running low on oil is a surefire way to damage the bar and chain.
2. Look for oil discharge from the bar tip when the chain is spinning (only test this in a safe environment, following all safety procedures, to see if the chain flings oil onto a clean surface).
3. If you think the oil system is blocked, check your chainsaw’s manual or consider cleaning the oiler ports to ensure a steady flow.

Good lubrication lets the chain move effortlessly around the bar, minimizing uneven friction and preventing wear that leads to crooked cuts.

Check and sharpen the chain

A dull or unevenly worn chain can make your saw drift off line. Even if the bar’s in good shape, the chain’s cutters need to be uniformly sharp and sized to pull straight through the wood. If some teeth are shorter or duller than others, the chain tends to pull left or right.

Steps to inspect chain condition

1. Ensure the chainsaw is completely off and secured on a stable surface.
2. Remove the chain from the bar if you haven’t already. Carefully examine each cutter (the sharp teeth along the chain) for chips or breaks.
3. Check the cutter length. If the cutters on one side are more worn than the other, your chain won’t stay balanced as it spins.

How to sharpen and even out cutters

1. Use a round file that matches the cutter’s recommended size (usually found in your chainsaw manual).
2. File each tooth using the same number of strokes to maintain uniform length and sharpness.
3. Work at the correct angle. Most chain manufacturers specify a filing angle, like 30° or 35°, to keep the tooth shape correct.
4. If needed, file the depth gauges (the small bumps in front of each tooth) using the recommended depth gauge tool, so each cutter bites into the wood at the right depth.

When each tooth is sharp and uniform, your chain should cut more consistently, pulling through the wood with less effort. If you need more guidance, check out our repair help section for troubleshooting advice and tips on tool use.

Examine and adjust the chainsaw bar

A misaligned or damaged guide bar is a common culprit when a chainsaw cuts unevenly. The guide bar is the long, flat piece that the chain loops around. If you’re not getting a straight cut, it’s time to inspect the bar carefully.

How to check for bar wear

1. With your chainsaw off and the spark plug cable disconnected, remove the chain and bar, following your chainsaw manual’s instructions.
2. Place the bar on a flat surface and use a straight edge to check both the top and bottom edges. Look for signs of bending or warping. Even a slight bow can send your chain off course.
3. Inspect the bar rails (the raised edges that guide the chain). If these surfaces are uneven or heavily worn, your chain can tilt to one side.

If you notice damage, you can dress the bar rails using a flat file, lightly smoothing them until both sides are even. Small nicks or burrs on the bar can be filed away, but if you find major cracks or severe bending, you might need to replace the bar. If you decide to replace parts and need model-specific guidance, you can check out how to find your chainsaw’s model number for accurate matching.

Confirm bar alignment

1. Reattach the bar and tension the chain as usual (making sure the saw is still off and the spark plug cable disconnected).
2. Visually inspect the chain to ensure it’s sitting properly in the bar groove and not tilted.
3. If the chain leans to one side, you may need to reposition the bar mounting studs or reseat the bar itself so it sits squarely against the saw’s housing.

You want the chain to track straight along the length of the bar with no wiggle. Always double-check your chain tension settings after making any bar adjustment to keep the chain snug but not too tight.

Check out the chain drive sprocket

The chain drive sprocket, located behind the clutch drum, meshes with the drive links of the chain. Over time, the teeth that engage the chain can wear down or warp, throwing the chain off-center. A worn sprocket might cause the chain to skip or track unevenly, leading to cuts that veer left or right.

Visually inspect the sprocket

1. Turn off the chainsaw and remove the side cover to access the sprocket. Consult your manual for details on how to remove the clutch drum and sprocket, as these can vary by chainsaw make.
2. Examine the sprocket’s teeth: they should have sharp, defined edges. If they look rounded, chipped, or dented, this can cause chain misalignment.
3. Check for grooves cut into the sprocket. Significant grooves mean heavy wear.

Replace a worn sprocket

1. Remove the old sprocket from the crankshaft as outlined in your chainsaw’s manual. This might involve removing a retaining clip or small washer.
2. Align the new sprocket onto the crankshaft so the splines fit properly.
3. Reinstall the clutch drum, bearing, and any washers, following the reverse steps of removal.
4. Make sure the chain drive links seat correctly on the new sprocket before tightening everything down.

When you replace the sprocket, it’s often a good idea to replace the chain at the same time, since a worn chain on a new sprocket can speed up wear. This helps maintain a smooth fit between the chain’s drive links and the sprocket teeth.

Still have questions? We’re here to help

We hope these tips help you tackle crooked cutting problems on your own. There’s something satisfying about restoring your chainsaw’s performance without outside help. Whenever you need parts or resources, remember you can always visit AppliancePartsPros.com. Stay connected with us on Facebook and Twitter to keep up with our latest DIY repair content. If you’ve got any questions or need further assistance, feel free to contact us at AppliancePartsPros.com anytime.