Getting Firewood Cut to the Right Length With a Chainsaw
Most people grab their chainsaw and start bucking rounds without measuring. They end up with lengths that don't fit their stove or smoker. The process is straightforward once you stop guessing. Mark your desired length on the log before you cut. Use a tape measure, a piece of wood cut to length, or even a simple marker with measurements on it. I spent three winters burning cord of wood that was two inches too long for my insert. The wood would stick out, block the door from closing properly, and I'd spend more time trimming it than actually splitting it. What I wish I'd known from the start was that marking a reference board and sticking it to the bar makes the whole operation take half the time.
Chainsaw Firewood Length Guide
The most common lengths you'll encounter are 16 inches, 18 inches, and 20 inches. Your stove manufacturer usually specifies the optimal size. Check the firebox opening measurement. Subtract about an inch for clearance, and that becomes your target cut length. If you have an outdoor wood furnace, you might be cutting 24-inch rounds instead. One thing beginners miss is that wet green wood shrinks as it dries. If you're cutting hardwood like oak or hickory to exactly match your stove's firebox, the wood will shrink about a quarter inch per inch of diameter after seasoning. That's usually fine, but it means you can cut slightly oversized and let the drying do the work. Softwoods shrink less, maybe an eighth of an inch per foot, so they're more forgiving. Another counter-intuitive point: cutting length matters less than consistency. It's better to have all your rounds at the same length, even if that length isn't the absolute ideal for your stove. Uniform piles split faster, stack better, and load predictably. I've seen people agonize over getting every piece to exactly 15.5 inches when their stove actually fits 16-inch rounds fine. The time spent measuring every single piece could be spent stacking or moving on to other chores.
Measuring Techniques That Actually Work
A tape measure works, but it's awkward with a running chainsaw in your other hand. A better method is a length gauge. Take a scrap 2x4, mark your desired length on it with a pencil, and tape it to the top of your chainsaw bar near the front handle. When you position the gauge mark at your cut line, you're done. No measuring, no guessing. Some sawyers use a second person to call out measurements. This is faster for high-volume work but introduces human error. I've had friends who rely on callers end up with rounds varying by an inch or two because the caller wasn't looking at the cut line, just the tape. For production work where you're cutting 50+ rounds per session, the gauge board method reduces this error significantly. Edge case I ran into last year: cutting short lengths on a curved or bell-shaped log. The taper means one side of your cut will be a different diameter than the other. If you're measuring from the outside edge, your inside measurement might be off by half an inch or more. The workaround is to measure through the center of the log, or just eyeball it since the length variance in curved wood rarely affects stove loading.
Get the Full Details
When Length Doesn't Matter As Much As You Think
If you're splitting wood for a traditional open fireplace rather than a sealed insert or stove, length tolerance is looser. Open fireplaces can handle a range of sizes. The key constraint here is that the wood needs to fit through your woodshed door and into your storage area. I've seen people cut beautiful 16-inch rounds only to realize they can't carry them through their back door. Measure your thresholds before you start bucking. Another scenario where exact length is less critical: wood destined for a wood chipper or biomass boiler. These machines handle variable lengths without issue. In fact, slightly longer pieces sometimes feed more reliably in certain chipper designs. The tradeoff is you're not creating stackable firewood anymore, so the length debate becomes irrelevant. Here's the blunt truth about chainsaw bucking for firewood: your chainsaw's bar length limits your log diameter, not your cut length. A 16-inch bar can handle logs up to about 14 inches in diameter comfortably. For longer rounds, you just need a longer bar, which means a bigger chainsaw. The engine power requirement scales with bar length, so cutting 24-inch rounds requires a more powerful saw than cutting 16-inch rounds, all else being equal.
Common Mistakes That Waste Time
Cutting without a stop is the biggest mistake. You think you're making 16-inch rounds, but your first cut is 15 inches, your second is 17, and by the tenth piece you've got five different lengths. This makes stacking nearly impossible and wastes time measuring each piece afterward. Set your gauge and commit to it for the whole batch. Another error: measuring from the wrong point on the bar. The effective cut length changes depending on where you place your mark relative to the guide marks on the bar. Some bars have etched measurements; others don't. If you're using a reference board, make sure you're measuring from the same point every time. Inconsistency here adds up fast over a full cord. And here's something nobody warns you about: chain brake placement affects your cutting position. If your chain brake is positioned awkwardly on your particular saw model, you might find yourself leaning in an uncomfortable position to see your cut line. This leads to rushing cuts or inaccurate measurements. Test your stance with the saw off before you start bucking. Adjust your grip or position if needed.
The reality is that for most homeowners cutting firewood for personal use, spending five minutes setting up a length gauge saves twenty minutes of measuring during the actual bucking process. The difference becomes more pronounced the more wood you're processing. For a single face cord, the time savings might be marginal. For a full cord or more, the setup pays for itself immediately.
