When you add a pint of pre-mixed fuel to an average chainsaw, it will run for 15 minutes continuously. A battery-powered chainsaw has a run time of up to 13 hours which can easily take you through your workday without a recharge. STIHL claims a forty-five minutes runtime with their chainsaws.
The life expectancy of any chainsaw is determined by its use, not by a pre-determined manufacturer specified lifespan or expiration date.
The cutting speed and the cutting time of an average chainsaw
An average chainsaw piston moves up and down 20,000 times per minute. The piston speed of an average chainsaw is 2500 square feet per minute.
The average chain sliding speed across the bar is 5000 square feet per minute. It means your chain will run at 55 to 60 miles per hour or 1 mile per minute which is equivalent to 88 square feet per second. The chain rotates for about 1300 times per second and the sprocket rotates about 1 million times in 24 hours.
To calculate the exact chain speed of your saw, find the chain pitch and multiply it by 2. Multiply the number found by the number of the teeth on your chain. Multiply the number found by your saw rotations per minute (RPM).
In this way, you will find the speed of the chain in inches per minute, divide it by 12 to find out feet per minute and divide it by 720 to convert to feet per second. Let us now try out a more sophisticated estimate. Let us suppose you have a tree that is 30 cm or one foot in diameter and your chainsaw makes a cut of 0.5 mm or 0.02 inches into the wood with each pass of the chain.
It means that your chain needs to pass through the wood six hundred times, thirty cm = three hundred mm and it takes two chain passes to remove each mm. If you are using a powerful chainsaw with a rotational speed of about two thousand eight hundred rotations per minute (2800 RPM) or three thousand rotations per minute (3000 RPM), the chain will make six hundred passes in just twenty seconds. Let me now compare this time with the cutting speed of a hand saw.
How long would this take with a handsaw? Let us suppose your hand saw has teeth of the same size as your chainsaw’s. Let us suppose they are roughly the same length as the chainsaw (half as long as your chain). You still need to make six hundred passes through the wood.
Let us suppose you can make one complete pass of the hand saw each second and keep up that speed constantly. Then it will take, at a minimum, six hundred seconds or ten minutes. In practice, as the saw slips out of its groove from time to time it will take longer.
This is a guesstimate, a back of the envelope calculation but I hope you got the idea. Using a chainsaw is certainly many, many times faster probably five to ten times faster than using a good handsaw. The simplest way to find out the sprocket speed of your chainsaw is to count the number of its teeth.
Your chainsaw has a toothed sprocket attached to its crankshaft. To calculate the speed of your chainsaw, you must divide the number of the teeth on its input gear by the number of the teeth on its output gear.
What is the run time of a battery-powered chainsaw?
A battery-powered chainsaw is cordless and noiseless. It does not depend upon a non-renewable fuel, and it does not exhaust any harmful emissions. It has advanced features including LED visual and audible recharge alert, a temperature sensor to avoid overheating and a rain guard.
Let us now explore the run time and recharge time of different batteries:
i) The AR 1000 backpack battery delivers an exceptional run time of up to 7.5 hours.
ii) The AR 2000 backpack battery delivers an exceptional run time of up to 11 hours.
iii) The AR 3000 has an exceptional recharge time to 100% capacity within just two hours and forty minutes.
Tim Johnson, a logger says: “My setup includes the STIHL AP 300 battery. This is their 36-volt lithium-ion, 6.0 Ah battery. STIHL claims a forty-five minutes runtime with a chainsaw and battery, but it is hard to equate what runtime minutes mean with a chainsaw.
Let us find out how many cuts I can make. I found a large section of the oak tree that had a consistent branch diameter of roughly 10 inches. Now, with a freshly charged battery, I made approximately 43 (it was 42 ⅞) cuts from the oak limb.
Frequently asked questions (FAQs)
1. Is ethanol harmful to my chainsaw?
Yes, ethanol is very harmful to the engine of your chainsaw. Ethanol will dissolve the gum deposit and varnish deposit that had previously settled down in your engine. This thick mixture will clog the small fittings and filters inside your chainsaw.
Ethanol is responsible for creating a lot of corrosion inside the fuel system because it mixes with the moisture in the air. Ethanol absorbs a lot of water and settles down at the bottom of the fuel tank. Engine failure occurs when a layer of gasoline is left on the top which has a lower octane level than the original ethanol-gasoline mixture.
The fuel system draws from the bottom of the fuel tank and when it uses water and ethanol instead of gasoline and oil, the system will fail because that mixture is too thick to pass through easily. Gasoline sold in the USA has ethanol in it. The law allows a maximum limit of 10% ethanol content in the fuel for small engines.
You must always use 89 Octane in your chainsaw. Always buy as little fuel as you can finish within 2 months. Ethanol-free and high-octane synthetic oil can be stored in the original container for up to 2 years.
2. Why does a chainsaw flood?
Your chainsaw will flood when you try too many times to start it in a choke position. You must learn to start it by reading and following the instructions given in the user manual. You must always remember that when placing the switch control to the full choke setting, more fluid fuel, and less air will flow into the combustion chamber to create a higher chance for ignition.
If you pull the rope more than 2 or 3 times in this situation you may flood the engine of your chainsaw. You must move the Master Control Lever or the choke lever from its full choke setting after 3 or 4 pulls even if the engine has to fire. When you move the lever to the next setting, the half choke or part throttle position, it will allow more air into the combustion chamber and help in resolving the flood condition.
3. Why does my chainsaw leak bar oil?
The oil is distributed inside the bar rails when it is circulated by the oil reservoir of your chainsaw. The normal quantity of oil is 0.3 to 0.5 ounces. As soon as your chainsaw stops, the oil will be pulled down because of gravity and settle down at the bottom of your bar.
Naturally, the oil will start seeping from the bottom of the bar, chain and the drive sprocket. The oil will continue to seep because anti-flinging material which is lithium is mixed in it at the refinery. Lithium will give it a very thick consistency so it will flow slowly.
If you want to store your chainsaw for a long time and you find it seeping oil for many days then the problem is with the vacuum relief valve. The vacuum relief valve is situated between the bar and the oil output hole on the side of the engine of your chainsaw. The vacuum relief valve has an internal spring and a ball pressed against the output hole of the casing of the valve when the fuel tank develops a vacuum from the oil being pumped out.
When this ball is pulled away from the output hole, it will allow the air to enter into the fuel tank thus breaking the vacuum, so that the oil will continue to flow to the bar and chain of your saw. After the vacuum is relieved, the spring pushes the ball back against the output hole of the valve casing. Sometimes, between the ball and a hole, there is a lot of dust, dirt, and grease.
This will cause the oil to keep seeping because there is still some amount of vacuum in the tank which will prevent the oil from moving freely when you shut off your chainsaw. To remove the dust and dirt sticking in the hole, you must take a pin or a needle and push it six to seven times into the hole of the valve. To prevent any damage and oil from leaking you must remove all the fuel from the fuel tank when storing the chainsaw for a long time.
4. Is it important to wash the chainsaw chaps before every use?
The chainsaw chaps are designed to protect your lower body from the cuts of a rotating chain. They are made up of cut retardant material which is often compressed when it is shipped and stored. When you wash them before every use, the protective pads become fluffy and helps to prevent you from cutting yourself.
You must always read and follow the washing instructions otherwise you will damage their cut retardant property. The chainsaw chaps are strong enough to control the movement of the sprocket and the chain. The level of the protection depends upon the speed and torque of the saw at the time of the contact with the body part.
You should never dry clean your chainsaw chaps, instead, you should tumble dry them only. You should never iron, bleach or use fabric softeners while washing your chainsaw chaps. It is recommended to machine wash them with warm water and mild detergent.
Make sure that the zippers, loop and hook fasteners are closed. Measure the length of your legs carefully before buying a pair of chainsaw chaps for yourself. If you buy a short one a part of your legs will be left exposed which is very dangerous.
The ideal chap length is between the top of your boot and second or third lace hook. It should not cover your boot toe.
5. How to store my chainsaw for more than one month?
First of all, you must dismantle the cutting part of your chainsaw. Clean the air filter, cylinder fins and the spark plug of your chainsaw. Apply a small layer of oil on the metal parts to prevent corrosion and rusting.
You must replace the old spark arresting screen of the muffler in your chainsaw with a new one. Make sure the fuel tank is empty and not a single drop of oil is left behind in it. You must run the engine of your chainsaw for a couple of minutes to make sure that the fuel system is completely dry.
You must run the engine at the idle speed, do not operate the throttle until the engine stops.
6. How many kinds of chainsaws are used commonly?
There are 5 different kinds of chainsaws that are used commonly:
i) Battery chainsaw: It is a lightweight, portable and instant starting machine.
ii) Electric chainsaw: It has infinite run time. It can start instantly and is lightweight.
iii) Farm or ranch chainsaw: It is used for storm cleanup and firewood cutting.
iv) Homeowner chainsaw: It features advanced technology and general German engineering. Its Quickstop feature is a chain brake system that is designed to stop the chain in a fraction of a second and can be activated by inertia in the event of a kickback. A homeowner chainsaw has many more features including anti-vibration technology for maximum user comfort.
v) Professional chainsaw: It can handle the toughest task easily.
6. How do I measure the speed of my chainsaw?
You can measure the speed of your chainsaw by using a tachometer. The tachometer is an instrument used for measuring the rotation or revolution speed of the crankshaft in your chainsaw. The tachometer measures revolutions per minute (RPM) of the chainsaw.
The older models of a tachometer used a needle and a dial to show the readings, while today’s highly advanced tachometers have a digital LED display where they show the reading. It is a simple method.
You have to clamp the tachometer to the spark plug wire of your chainsaw. The tachometer will measure how many times the spark plug fires every minute. Each time the spark plug fires, the engine crankshaft of your chainsaw makes one revolution.
The tachometer reading is a direct measurement of the engine speed of your chainsaw. If you have a digital tachometer, you will not even have to connect it to the wire. You can measure the speed by just holding it near the spark plug of your chainsaw.
7. What maintenance should I perform daily on my chainsaw?
You must clean the outside of your chainsaw daily. You must check that the throttle control and the throttle lockout are working safely. You must make sure that your chain brake is working safely, if the chain catcher is damaged you must replace it at once.
You must turn the bar daily. You must also make sure that the lubrication hole is not blocked. If your bar has a sprocket tip then you must lubricate it daily.
8. What maintenance should I perform weekly on my chainsaw?
If your chainsaw has no catalytic converter then you must weekly check its cooling system. You must check the return spring, the starter cord, and the starter. Make sure that the vibration damping parts are not damaged.
You must properly lubricate the clutch drum bearing weekly.
9. What maintenance should I perform monthly on my chainsaw?
You must check the chain brake band monthly and if it is less than 0.6 mm thick then replace it at once. You must check the clutch spring, the clutch drum and clutch center of your chainsaw. You must clean the spark plug and make sure that there is a 0.5 mm gap between the electrodes.
You must also clean the carburetor of your chainsaw from outside only. To conclude this blog post, I would say that you can run your chainsaw for fifteen to forty-five minutes non-stop after adding a pint of fuel to it. Proper maintenance and careful storage will extend the lifespan of your chainsaw. You must always read the user manual carefully before any repair and seek the assistance of a professional expert in case of any mishappening.