In this first Chainsaw Basics post, before we get our hands on an actual saw it’s a good time to better understand what’s actually going on when the noise lets loose and the chips start flying. We’ll begin by staring down the worst-case scenario and the 800-lb. gorilla in the room — kickback.
Primal fear: It hangs in the very air surrounding a chainsaw. Don’t believe me? Tell someone you’re going to take up a leisure activity involving a chainsaw and see what kind of reactions you get. Try handing one to an unsuspecting visitor to the shop. The snap reaction you’ll witness is a base human response to an object that is violently loud, powerful and potentially deadly. However, base reactions are just that — base. A more correct word is uneducated. So let’s fix that.
Kickback is really just a quick study in elementary physics. When an object in motion is stopped and the force behind that object is still supplying energy, there is an equal reaction in the opposite direction that uses your grip on the saw and the point of obstruction to determine the direction. Simply put, kickback is a transfer of momentum.
There are two types of kickback, each with its own issues.
- Bar tip dig in
- Pinching the bar
Bar tip dig in is probably the most dramatic. The chain on your saw is moving in a circular motion. It rotates forward away from you, goes around the tip of the bar where it changes direction, and starts moving back towards you. The top quarter of the nose where it changes direction is called the kickback zone. If your chain comes in contact with an object in this location, the saw will kick up and back towards your face. Henceforth this shall be known as “bad.”
Pinching the bar happens when the chain is pinched between the wood by the weight on either side of the bar during the cut. If you stop the chain on top of the bar while cutting from below, the saw kicks out; if it happens on the bottom of the chain while cutting down, the saw will slam forward.
The amount of force, how fast the chain stops, and where it’s being stopped all determine how severe and what direction the kickback will be. If the chain is stopped suddenly the kickback is epic. Slow it down a touch and it’s just a little hiccup.
The good news is, our goal is not to drop redwoods but to doing a bit of carving. This changes that physics equation we were talking about earlier.
- A carving bar or dime-tip bar has a much smaller kickback zone on the tip. The smaller zone means less chance of it getting caught.
- The 435 is a 2 hp saw, not 8 hp like the big dogs. This means less force is pushing back on you. Though it’s still enough to mess you up.
- Cutting branches or trees that are under strain or load is what normally causes bar pinching. The piece you will be carving will be smaller and mounted properly with as little inherent stored energy as possible. Less stored energy means less possibility for movement and pinching.
You can still mangle yourself carving, but you can begin to see how lessening the potential problem areas starts to focus these hazards to a more manageable size. However, these are not the biggest factors that keep you safe.
One of the biggest things you can do to help minimize kickback is to keep your damn hands on the saw. Maintain a solid grip on the rear and front handles at all times. You can’t slow down or redirect a wild swing of motion if you aren’t in control of the tool in the first place.
Another thing you can do to minimize kickback is to plan your cuts. Don’t just hack away at a log or stump. Plan the cut in your mind and take a second to practice the motion you want to accomplish. Are your feet and hands set correctly? Can you reach the entire arc of the cut without repositioning? Are you standing to the side of the cutting plane? Are you trying to do a cut above your shoulder? These little checks will help you gauge whether what you plan to do is intelligent or not.
It seems like a no-brainer, but keep your chain sharp and tensioned properly. A dull or loose chain will grab wood under the best of circumstances and create all kinds of fun stories to tell your friends. You might even get a cool nickname like “stumpy” or “blood-n-guts” out of the deal, so yeah, bonus.
Wear the proper safety gear — ’nuff said. Though in all honesty, we’ll do a post over that later as well.
The last area to be aware of is attitude. I’ve witnessed three major states of mind when people pick up a chainsaw; moronic disregard for one’s own safety/not respecting the tool, unholy fear that it will somehow turn into a snake and strike, and of course educated operation. The latter is to be preferred.
Chainsaws are just tools like anything else — extremely powerful tools, but still tools. They should not be feared or given wide berth because of some bit of gory lore that somehow, through the same evil sorcery that brought Christine to life, chainsaws injure all those around them: They don’t. Nor should they be treated as toys — they’re not. Almost all chainsaw-related injuries can be tracked back to the ignorance/inattention of the operator or poor saw maintenance. So don’t do that.
In the end, objects themselves are not dangerous until we start interacting with them. Our own skill and knowledge is what turns a stick into a lever or rock into a counterweight. A chainsaw is a force-multiplier created to give one person the strength and speed of many. The tradeoff for all that power is the danger that it can be turned on its master. Learning how and why that turnaround happens grants us the ability to harness its strength and greatly reduces the likelihood of injury.
Next up, we will be running down the saw itself and how to set it up.