Chainsaw Cuts Crooked or Pulls to One Side: Chain, Raker, and Bar Checks

A chainsaw that curves through a cut usually means uneven chain sharpening, not a bad bar. Here is the checking order that actually finds it.

Walt Emerson — Home Equipment Repair Technician · Updated September 23, 2026 · 6 min read

Quick answer: A chainsaw that curves through a cut instead of running straight is telling you the two sides of the chain are not cutting equally — one side is taking a bigger bite than the other. In the large majority of cases the cause is a hand-filed chain where one row of cutters ended up longer or sharper than the other, not a bent bar or a damaged saw. Confirming that with a simple flip-the-bar test before buying parts saves both money and a chain that gets filed crooked twice.

Start with the chain, since it causes most crooked cuts

Pull the chain off or loosen it enough to inspect each cutter closely. Compare the exposed cutting edge on the left-hand teeth against the right-hand teeth — length, shine, and angle should look the same side to side. A row that looks shorter, duller, or more rounded than its opposite number is the most common reason a saw pulls: that side removes less wood per pass, so the sharper side pulls the bar toward the dull one as it cuts. This is exactly why a saw that was cutting straight before a hand sharpening often starts curving right after one — a few extra file strokes on one side during that sharpening session is often all it takes.

Run a finger carefully along a few teeth on each side, chain stopped and saw off, and compare how aggressively each one catches on a fingernail or a scrap of wood. It is a rough test, not a measurement, but a clear difference between the two sides usually confirms what a visual check already suggested.

Fix uneven sharpening by counting, not guessing

The reliable fix is to stop sharpening by feel and start sharpening by count. Pick a consistent number of file strokes, use the file diameter and holder angle the chain calls for, and apply that identical stroke count to every cutter on one side before switching to the other. Mark the first cutter with a paint dot so you know where the pass started and do not lose count partway around the loop. If the saw has been pulling for a while, expect the two sides to need different amounts of correction on this first pass — the point is to bring both sides to the same length and angle, even if one side needs a few more strokes to catch up, then keep the stroke count matched on every sharpening after that.

A filing guide or clamp-style sharpener that references the top-plate angle removes most of the guesswork here, especially for anyone still learning to read the angle by eye. Whatever tool is used, the goal is the same: both rows of cutters ending up the same length and the same angle when the pass is done.

Depth gauges (rakers) can throw off the cut too

Every cutter has a small raised tab called a depth gauge, or raker, just in front of it. The raker controls how deep that cutter can bite into the wood on each pass — file the rakers down and the chain takes a bigger chip; leave them too tall and the chain barely cuts at all. If the rakers are not the same height from cutter to cutter, especially between the two sides, the bite size becomes uneven along with the sharpening, which compounds a pull instead of correcting it. Use a depth gauge tool matched to the chain's pitch, laid flat across the cutters, and file down only what sticks up above the tool before rounding the front edge of the raker.

Do not file rakers lower than the chain manufacturer's spec to make the saw feel faster. A raker filed too low lets the cutter take an oversized bite, which makes the saw grab harder than it can control and raises kickback risk. Most chains specify roughly 0.025 inch for hardwood and 0.030 inch for softwood, measured with a depth gauge tool rather than eyeballed — check your exact chain's spec sheet first.

The flip-the-bar test separates a chain problem from a bar problem

If a careful, evenly-counted sharpening does not fix the pull, stop suspecting the chain and start suspecting the guide bar. Guide bars wear unevenly when they always run the same side up, because the bottom rail carries most of the load during a typical cut while the top rail sees less wear. Over time that turns a straight bar into one with a slightly sloped rail, and a sloped rail steers the chain off-center no matter how well it is sharpened.

Flip the bar over — swap which rail faces down — and make a few test cuts. If the saw now pulls the opposite direction, the bar's worn rail was the cause, not the chain. If it still pulls the same direction after flipping, the chain, or an unevenly worn drive sprocket, is still the more likely culprit and deserves another look before spending money on a new bar.

Inspecting the bar rails and body for damage

With the chain off, sight down each rail from the tip toward the powerhead. The two rails should look parallel and even; a rail that visibly dips, flares, or shows a shiny worn groove wider than the rest is no longer supporting the chain evenly. Also check the bar body for a bend, most often from a pinch in a cut or the tip catching something solid — lay it on a flat surface and look for daylight under any section that should sit flush.

A bar with uneven rail wear can sometimes be dressed back closer to square with a flat file, but a bar that is actually bent, or one with rails worn past the manufacturer's minimum, should be replaced rather than repeatedly compensated for with sharpening tricks.

Rule out the drive sprocket and a mismatched chain

A worn or damaged drive sprocket — the toothed wheel that pulls the chain around the bar — can also produce an uneven, jerky feed that shows up as a curving cut, especially if only some of its teeth are worn. Spin it by hand with the chain and bar off and look for teeth that are visibly more rounded or hooked than the others. While apart, also confirm the chain's pitch and gauge actually match the bar and sprocket; a close-but-wrong match can ride off-center in a way that mimics a sharpening problem.

The order that finds the cause fastest

Compare both rows of cutters by eye and by feel for a length or sharpness difference.
Re-sharpen with a matched stroke count on each side, using a filing guide if you have one.
Check every raker against a depth gauge tool and correct any that sit noticeably taller or shorter than the rest.
Make a test cut. If the pull is gone, you are done. If it remains, flip the bar and cut again.
A pull that changes direction after flipping the bar points to the bar's worn rail; a pull that stays the same direction points back to the chain or the drive sprocket.
Inspect the bar rails and body for wear, a bent section, or damage that filing cannot correct.

Before your hands go anywhere near the chain

Keep the chain brake engaged and the saw off, with the spark-plug lead pulled or the battery removed, for every step of this inspection. Wear cut-resistant gloves while handling the chain; the edges stay sharp enough to cut even when the saw is off. A saw still pulling hard after chain, raker, and bar checks, or one where the pull is severe enough to fight for control, is a reasonable point to have a saw shop look at the sprocket, clutch drum, and bar mounting rather than continuing to guess.

Why a straight cut matters beyond convenience

Fighting a pull with extra hand pressure is exactly the kind of grip that increases fatigue and reduces control if the saw kicks back, and it wastes more of the log to an uneven kerf while wearing the chain and bar faster on the side taking the heavier bite. Comparing both sides of the chain at every sharpening, checking rakers with a proper tool instead of by eye, and flipping the bar on a regular schedule keeps a pull from developing in the first place instead of chasing it down mid-season.

Continue with related checks: Chainsaw Won’t Start: Gas and Battery Saw Decision Tree Chainsaw Starts Then Dies When Throttled Chainsaw Chain Won’t Tighten or Keeps Getting Loose

Sources and safety references

FAQ

Is a chainsaw that cuts crooked dangerous to keep using?

Treat a strong or sudden pull as a stop-and-inspect situation rather than something to muscle through, since fighting the saw's natural direction with extra hand pressure reduces your control if the saw kicks back. A mild pull you are actively tracking down while sharpening correctly is a lower concern than one that is getting worse or appeared suddenly mid-cut.

How can I tell if the problem is the chain or the guide bar?

Flip the guide bar over and make another test cut. If the direction of the pull reverses, the bar's worn rail was the cause. If the saw still pulls the same direction with the bar flipped, the chain, or a worn drive sprocket, is the more likely source.

What raker (depth gauge) height should I be filing to?

Check the spec printed on the chain's packaging or the manufacturer's chart for that exact chain, since pitch and intended use change the number. Roughly 0.025 inch for hardwood and 0.030 inch for softwood is a common range, measured with a depth gauge tool rather than by eye, and filing rakers lower than specified increases kickback risk rather than just making the saw cut faster.

Can a bent guide bar be straightened instead of replaced?

Minor rail wear can sometimes be dressed flat again with a file, but a bar that is visibly bent along its body, or one with rails worn past the chain manufacturer's minimum thickness, should be replaced. Continuing to compensate for a bad bar with chain adjustments tends to wear out chains faster without fixing the underlying pull.

How often should I flip my guide bar to prevent uneven wear?

A common habit is flipping the bar at every chain change or full sharpening session, since the bottom rail carries more load than the top rail during normal cutting. Saws used heavily for extended cutting sessions benefit from flipping even more often than that.