Getting measurements on your chainsaw bar and chain can seem easy at first. With the mass amount of different chain saw brands, sizes, and types, your bound to get different bar lengths on you unit.
Before we start, make sure you have a basic working knowledge of your chainsaw and it's operations. Depending on the nature of work, will determine the size of the chainsaw bar and what it can handle.
For instance, smaller chainsaws have smaller engines, which will limit the speed and power of your machine. Typically the size of your chainsaw bar for smaller to medium saw's will range from 12" to 20" while your larger models start from 20" on up.
In this guide, we will breakdown things to consider about your chainsaw bar and chain, in addition to how to measure them in 3 easy steps. But first take a look at our recommendations on what guide bar length you should use based on application.
Bar Length (Inches)
Trimming & Pruning
8" to 16"
Small Tree Cutting
12" to 14"
Medium Tree Cutting
14" to 16"
12" to 14"
Light/Medium Fire Wood Cutting
14" to 18"
Large Tree Cutting
18" or Larger
1). Safety First! Make sure the chainsaw switch is in the off position and remove the spark plug. This will eliminate accidental startups.
Also if you just used your chainsaw let it cool down for a while before trying to measure your guide bar. This is crucial so you won't get burnt from your machine when approaching the engine.
2). Next, place your chainsaw onto a flat surface such as a table or a workbench and position it upright. You will need a tape measure before you can proceed to the next step.
3). Take your tape measure and get the distance from the tip of your saw blade to where it enters the housing. This measurement will determine the size of your bar, which is also known as the cutting length.
1). Always round to the nearest whole inch after measuring your chainsaw bar so that you get an accurate reading. For example, if you measured 15 3/4"(inches) then you will need to round up to 16".
2). Keep in mind that the reading you measured is not the actual bar length! If you want this value you must detach your bar from the saw and measure it in it's entirety.
Four of the most important attributes to focus on with your chainsaw bar and chain is the cutting length, gauge, pitch, and finally the tooth count. Each one of these items can be found on your guide bar to help identify it's size.
The cutting length which is also known as the guide bar, is the actually length you will use during your saw's operation. This area consists of when the front of your chainsaw body meets the emerging bar, to the tip of your chainsaw nose.
The gauge of a chain is equal to the width of the groove on the guide bar, that is determined by measuring a section of your drive links that fit into it. Matching the right chain gauge is very important to your chainsaws operation.
Next up is the pitch. It is determined by measuring the distance between any three rivets from center to center then dividing by two. Pitch helps improve your accuracy and precision while cutting.
Tooth count, also known as drive links represent how many links are on your chainsaw chain. The drive links are the pieces on your chain that stick down and resemble shark teeth. As a side note the greater the distance between drive links the more aggressive cut's you will get.
First, in order to determine the size of your chain you must first know the number of "drive links", "pitch", and finally the "gauge". We covered these terms earlier above in our article, if you forgot what each of these attributes mean.
1). First, stretch you chain across a flat surface and begin to count the number of drive links around the chain. Once you have added up the links record this number since you will need it later in your final results.
2). Our next step is measuring the pitch. This can be achieved by measuring between any three rivets center and then dividing by 2. Record this number as well, and move on to the final step.
3). Last, you must determine the chainsaw gauge which is equal to the width of the grove in your guide bar. There are two methods this can be done by. One is with a measurement tool called Vernier Caliper and the other is what is called the Coin Technique.
In this guide we will review the coin technique since it requires no tools. However; watch the video below on how to measure a chainsaw chain to get a better idea of concepts and terms.
The coin method is a measuring tactic to give you an approximation on your chainsaw gauges width. It is done by placing a quarter, dime or penny in between the guide bar grooves until one of those options fits comfortably or snugged.
Below is a representation on what coin size width is equal to in terms of its gauge.
Chainsaw Chain Length=Total Drive Links+Pitch+Gauge
To answer this question depends on several things such as your project requirements, what type of material is being cut, and your physical stature.
However; one quick tip to help determine the size of your bar, is to make sure it's length is 2" longer than the wood you plan on cutting. For example, if you plan on cutting a 16" small tree in one pass,then make sure your guide bar is 18" or longer would be recommended.
Below are the top causes of when it's time to replace your chain.
Kickback is caused when the tip of your guide bar hits another object, or when the bar gets pinched by the wood saw chain in the cut.
So as you can see, measuring a chainsaw chain and bar can be easily done within three easy steps. In fact, just knowing the gauge, pitch and tooth count makes this task simple enough without having to use any tools, besides a measuring tape.
If your a serious wood worker or just a hobbyist understanding this quick process will educate you on your equipment functionality moving forward.