A chainsaw is more than just the sum of all its parts, but unless all the parts are functioning correctly, the chainsaw becomes ineffective and even dangerous to a certain extent. The motor power, the grip of the chainsaw and its manoeuvrability are all important, but the bar is the key to the chainsaw being effective. Depending on the types of tasks you wish to perform, the length of the bar will vary.
A 12 to 16-inch bar is perfect for pruning trees or cutting rouge branches, but isn’t suitable for either cutting a tree down or harvesting firewood. On the other hand, a 20-inch bar is perfect for cutting trees and harvesting firewood, but will prove completely ineffective in garden maintenance tasks.
So, when you need to replace the bar, measuring it accurately is of paramount importance. If the measure is incorrect, it won’t fit properly in the chainsaw and the entire machine will become useless.
Measuring the chainsaw bar isn’t as simple as taking out a measuring tape. You need to understand a few things about how the bar fits into the machine. Then there’s the chain that wraps around the bar. You need to measure that as well.
The Process of Measuring the Bar
Before you begin taking down measurements, you need to take a few precautionary measures. Firstly, turn off the chainsaw and then remove the spark plug. The spark plug is nestled at the rear end of the machine, under the carburetor box. Remove the bolt that attaches the carburetor box to the chainsaw, then remove the spark plug. This is essentially an extra precaution to prevent any chances of the chainsaw accidently switching on during the process of measuring the bar.
Measuring the Cutting Length
You will need a solid, flat surface to place the chainsaw on. A stable surface will help you take accurate measurements. Now line up the measuring tape’s tip with the bar at the point where it comes out of the chainsaw. Making sure that you are holding the tape firmly, extend it to the final tooth at the end of the chainsaw bar. The number that you come up with is the cutting length of the bar. Round the number to the nearest inch. Most standard chainsaws have bar lengths between 12 and 20 inches. Ideally, you should repeat the measuring process a couple of times to be doubly sure of the measurement.
Measuring the Full Bar Length
Now you will have to open the body of the chainsaw to expose the hidden part of the bar. It’s not complicated at all. Use a wrench or a combination of sockets and ratchets to unscrew the bolts that hold the casing in place. Once you have removed it, measure the hidden part of the bar. This is a much smaller section. Adding this to the cutting length measured previously gives you the full bar length.
Putting It Back Together
You have the measurement of the cutting length and the full bar length, now you need to put it all back together. Begin with the casing. Attach it just like you opened it with the wrench. Then plug in the spark plug and screw on the carburetor box.
Measuring the Length of the Chain
You’re nearly done now. There’s just one more step to go. You have to measure the chain that wraps around the chainsaw bar. Before you begin, you need to familiarize yourself with a couple of terms.
- Tooth Count: This is the number of links that make up the chain.
- Pitch: Measure the length from the center of one rivet till the center of the third rivet (of any three consecutive rivets) and divide the number by two. You get the pitch.
The links are what helps the chain attach to the cog. You need to count the total number of links. Next you determine the pitch by following the process mentioned above. Add the total number of links to the pitch and you get the measurement of the chain. Make sure that the pitch of the chain is the same as that of the nose socket. This is important because a mismatch would mean that you don’t get the correct chain for your chainsaw. You also need to measure the chain gauge, which is essentially the width of the groove in the chainsaw bar.
The chainsaw bar and the chain are a unit. A badly fitted chain, because of incorrect measurement can have serious consequences. If, at any point, you feel that you’re not completely sure if you’ve got the correct measurement, then get your chainsaw serviced professionally. Remember that replacing a chainsaw bar and chain is a relatively costly affair in itself. So, spending a few dollars more to ensure that the chainsaw is completely safe to use post the replacement is money well spent. However, if you wish you do it yourself, then just follow the instructions detailed above.
Note that some chainsaw manufacturers incorporate essential information such as bar length, pitch and gauge in the model number itself, while others don’t. You can have a quick chat with a representative of the manufacturer to find out if the model number of your chainsaw has these details built in or not. It will make your task simpler. As mentioned earlier, you have nothing to worry about if this isn’t the case with your chainsaw. Simply follow the simple steps above and you will be set.
Finally, you need to regularly perform routine maintenance checks on your chainsaw. It’s an expensive machine and unless it’s cared for it can become ineffective and cost you a lot to either replace parts or buy a new one. The manufacturer’s user manual typically has the necessary standard maintenance procedure detailed in it. If you have any further questions, don’t hesitate to get in touch with them. In addition, always be safe while using a chainsaw. Protect your hands and eyes with a good pair of gloves and sturdy eyewear. Small chips of wood fly off while cutting and can damage your eyes. Safe cutting!