Chain Saws, Part 3
Safety and Operations
In the movie, ‘Dirty Harry’, Clint Eastwood, who plays Harry, does a narration about the 44-magnum pistol being the most powerful pistol in the world. When I was teaching about chainsaws, I mimicked that speech for my classes. Instead of a gun, I told the students that the chain saw was the most dangerous tool in the world. I also told them that a chainsaw, like a gun, becomes dangerous only when a human uses it.
My biggest problem when teaching how to operate a chainsaw safely and efficiently was the ‘un-teaching’ of bad and dangerous habits the students had learned from relatives and friends. Grandpa, Dad, and Uncle Pete taught some of those kids a lot of poor and risky maneuvers.
Before moving on, I ask you to review 2 short YouTube videos on starting a chainsaw. Please do this so I don’t have to repeat basic fundamentals of operation and besides, a picture is worth a thousand words.
Video 1 “Chapter 9, Starting Your Stihl Chainsaw” 4.06 minutes
Video 2 “How to start a Husqvarna Chainsaw” 3.03 minutes
Starting Procedure
1. Make sure the saws are full of fuel and oil, and the chain tension is adjusted and all bolts are tightened.
2. Never drop-start or push-start a saw.
a. When the engine fires or starts, you are holding it away from your body and the saw can twist in your hand.
b. It’s basic physics: The unit of power – 1 horsepower – is actually 990 pounds of power, AND if a saw engine is a 2 HP engine, that is almost 2000 pounds of energy you need to control with one arm.
c. Many operators don’t use the chain break when starting a saw, so think about that 2000 pounds of energy and a fast, rotating chain bouncing about your body.
d. I was taught (incorrectly) to drop-start, and luckily, I had the chain break on when the saw coughed and hit me on the back of the leg. NEVER AGAIN. I learned the correct way to start a saw.
3. The safest starting methods are placing the chainsaw securely on the ground and, with the chain break engaged, place your right foot on the bottom/rear handle guard. Place your left hand on the front handle and pull the recoil rope with your right hand.
4. The second method is called the ‘leg lock method’. Your legs are the strongest part of your body so by correctly placing the saw between your legs, you have the most control over the saw. With the break engaged, place the rear handle perpendicular between the legs and start the saw. Please don’t hold the saw parallel, I have more than one student do this and it can cause some real pain.
5. All new saws are right-handed. If you are left-handed, you need to learn to operate the saw right-handed. Trying to operate from the left-handed position will throw off your ability to safely and efficiently operate the saw, causing accidents and decreased operation performance.
6. The recoil rope or starter rope cord should be slowly pulled out until the cord has tension. Then pull the cord quickly about 16 – 20”. You may have to do this several times to start the saw. The recoil rope is not a ripcord – like on a parachute. In class, I had a student rip out 2 recoil ropes as soon as we got to the woods. He pulled the rope too far out, breaking it.
7. Very Important – Don’t release and snap the recoil rope back into the engine. Allowing the recoil rope to snap back into the engine will break the recoil spring and / or break the rope. Allow your hand to follow the rope as it rewinds, controlling the action.
Restarting a Warm Saw
1. Improper starting techniques will cause the engine to flood.
2. In the Stihl starting video, the narrator does a good job of explaining how to start a cold engine and the video shows a good view of the on/off switch, the choke setting, and locking the hand throttle. The procedure for starting a warm saw is the same.
3. Once the engine starts, the operator needs to release the throttle lock with a short, but quick release of the throttle trigger. Failure to do so can cause the saw to stop, only holding the throttle open, can destroy the clutch.
4. When the saw is warm, especially on Stihl saws, you need to follow this procedure to keep from flooding the engine. If you don’t understand what I mean, please review the Stihl starting video again.
5. To restart the Stihl and many other models, move the starting switch to full choke, lock the hand throttle and then move the starter switch to the RUN position. Then start the saw.
a. Going directly to the RUN position can cause flooding and starting problems. Please follow this procedure and you be surprised how easy the saw is to start.
Handling a Running Chainsaw
1. Remember the athletic stance your learned in PE class? Well, you will be using that stance to operate the chain saw.
2. Your body should always be positioned on the left side of the saw bar and chain.
3. Have secure footing.
4. Left hand on the saw top handle with your thumb wrapped under the handle and your right hand on the trigger.
5. 80% of all accidents occur to the left side of the operator’s body.
6. Never touch the chain to check chain tension with a saw running, even if the chain break is engaged. Pulling on the chain can cause the clutch to activate and the chain will begin rotating.
Cutting With a Saw
1. Never allow anyone to stand in front of you while you are cutting. IF the chain were to break and come off, it could kill the person in front of you.
2. Likewise: Never allow someone to stand directly behind you and keep them away from your work area.
3. Never reach over or under a rotating chain.
4. Never operate a chainsaw above your shoulders
5. Like all saws, the blade/chain should be at full speed before placing the chain on the surface to be cut.
6. When removing a chain from the cut, stop the chain by releasing the saw trigger. The chain should never be rotating when removing it from the cut.
7. When bucking a log, the log should be off the ground if possible.
8. If the log is off the ground, the chain should not drop more than one inch below the cut with the saw chain rotating.
9. To cut through the bottom of the log, control your saw chain by lowering it slowly through the final part of the cut.
10. Remember, the saw chain should be operated at full throttle during the entire cut. Don’t gun the throttle on and off as you cut. You will destroy your saw. Ask my neighbor, he still does this, even though he has damaged saw after saw.
11. Keep the saw in close to your body for strength and control.
12. With chaps, your right leg can help support the weight of the saw when resting or walking – but never with a rotating chain!
13. Use the chain break when moving from one area to another or when moving in a restricted area with limbs to climb over or under.
This accident occurred when the operator (our grandson) tripped backwards over a limb. As he fell, he pulled on the trigger of the saw as it landed on his leg. Luckily, he missed major blood vessels and permanent injury. The laceration was 10cm long and 2.5cm deep. It happened in the 'blink of an eye'. He was not wearing chaps at the time.
14. You don’t need to set the chain break when moving down a log when cutting firewood (each cut is 16 – 24”) and when moving down a log removing limbs if the area is free from obstacles.
15. When you get tired, take a break.
16. Only cut one piece of wood at a time, not two or three smaller pieces in layers (like a sandwich).
17. Plan your next cut before you move.
18. Don’t cut by yourself. At the very least, tell someone where you will be cutting and what time they can expect you back.
19. Before starting to cut, clear the work area.
20. If you drive into the work area, always be sure that the vehicle can leave the area easily in case of an accident.
White Finger Injury
1. White Finger Injury is a physical condition caused by the vibration of a saw, weed-eater, or other handheld tool.
2. It starts as a tingling in your fingers and hand which can become permanently damaged.
3. To help prevent White Finger Injury, use anti-vibration chainsaws, wear warm, dry gloves, dry and warm your hands when working in wet and/or cold weather.
Kickback
1. Watch Lowe’s Youtube video “How to Use and Maintain a Chainsaw” 3.46 minutes
2. Kickback occurs when the saw chain comes to a complete stop while the engine is still running at ‘wide open’ speed.
3. There are 3 types of kickback
a. The most common kickback occurs when the chain rounds the top end of the bar where it can take a larger cutting bite than normal, causing the chain to suddenly stop, throwing the bar and chain back and up at the operator.
i. A safety chain can prevent this type of kickback
ii. Earlier, I mentioned the left hand and thumb need to be wrapped around the front handle. With the thumb wrapped around the handle, your natural body mechanics will help guide the saw as it kickbacks to your left side away from the body.
1. If you keep your thumb riding on the top of the front handle, the kickback comes back toward your face and body.
2. If you get nothing else from this blog, please keep your left thumb wrapped under the handle.
b. Another type of kickback is from a pinched chain.
c. There is a pulling kickback when the top bar of the saw is used for cutting. The chain pinches and it pulls the saw and operator into the cutting zone.
d. Likewise, if the bottom side of the bar is used for cutting, a pinched chain will push the saw back at the operator.
4. Plan your cut, watch the end of the bar so as not to cut into another limb or log.
5. Your full concentration needs to be focused on your saw and what you are cutting. Don’t be day dreaming.
Saw Cutting Performance
1. The chainsaw is a tool. Let it do the work.
2. Always have the engine and chain at full RPM before placing the chain on the wood.
3. Allow the weight of the saw and the cutting motion of the chain do the work. Don’t force the saw through the wood.
4. Your left hand needs to be securely around the top handle, but don’t apply pressure or lay your weight on the saw to get it to cut faster – sharpen your chain.
5. Allow your saw to cut through the wood - don’t use a crosscut, sawing motion. It should be like a knife through butter.
6. On some cuts, you will rock the saw up and down, especially where the log is larger in diameter than the length of the bar and chain.
7. Watch your saw dust chips to determine if your saw is sharp. A sharp chain will produce large chips but a dull chain produces powder saw dust.
8. A dull chain is dangerous and the operator starts to apply pressure to the saw to help performance.
9. If the saw becomes pinched, shut it off and then remove it from the wood.
10. Plan your saw cut. Think how the wood is going to react to the cut. Is it going to drop off?
Become pinched? Cause the tree to rotate or move in a way which will pinch your saw.
Experience is a great teacher, but knowing basic safety fundamentals will reduce your chance of injury as you gain that experience.
Please be safe and if you don’t or are unsure how to cut with the saw--- get help from someone who knows how.
Safe cutting!
Bob
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