My chainsaw wouldn’t cut very well. It was driving me nuts!
In the end, it turned out, I had the wrong chain fitted! I had gone to a supplier and asked for a chain, for a Jonsered (Husqvarna) xyz chainsaw with a 15″ bar. They handed over a chain, I paid for it, went off home and fitted it… Wrong!
I discovered the chain gauge size was wrong. I had a suspicion, as the chainsaw was trying to curve round on a deep cut. Plus, I wasn’t getting a very efficient cut, the chain would get very hot and the guide bar was wearing unevenly!
Don’t always rely that the person behind the counter giving you the right part. To ensure your chainsaw performs at it’s best (and for your safety), go armed with knowledge so you can check you have the right part…
Please read the manufacturers safety advice.
Protective gloves are advisable when working on the chain…
You don’t actually need to measure anything, as long as the details (part numbers, etc) are stamped on the chainsaw guide bar and chain. However, you do need to know what the measurements mean?
I’m grouping the chainsaw guide bar and chain together, as they interact. If you’re buying a chain, you need to know what bar you have, and vice versa. Unless you’re buying a matching chainsaw bar and chain as a set, (then you just have to check the bar fits your chainsaw)!
There are basically 4 things you need to know, when buying a guide bar and 3 for a chain:
Measurements needed when buying a chainsaw guide bar or chain:
|What Info do I Need,
to Buy a Chainsaw Guide Bar or Chain?
|Items:||The Guide Bar||The Chain|
The guide bar and chain must match.
The guide bar and chain must match.
|3||The length of the Guide bar
This matches the length of the chain (the number of drive links).
|The number of drive links in the chain
This matches the guide bar length, (the nose sprocket & tail sprocket size).
|4||The Guide bar mount (or tail mount)
This matches the chainsaw body.
The three measurements look very similar (and they are). But they can have a slightly different meaning dependent on whether it’s for the bar or chain.
The measurements for the chainsaw Guide bar and chain must match.
The gauge is the size of the gully (or groove) that runs around the chainsaw guide bar. The chain sits in this gully and the size of the chain (the width of the drive links) and gully must match.
The gauge is:
The gauge is measured from the width of the chain drive link (the drive links are the teeth on the underside of the chain). This must match the chainsaw guide bar gully (or groove). The guide bar gully will be slightly wider to allow for the movement of the chain (but the measurement will be quoted as the same value as the chain)…
For more info, see: ‘The Chainsaw Chain & Guide Bar Markings:‘.
In engineering, pitch is defined as:
“the distance between regularly spaced objects”
As an example, the peaks (or troughs) of a thread on a bolt.
However, a chainsaw chain is made up of several different parts. Therefore, to obtain ‘the distance between regularly spaced objects’, the Pitch is measured by:
“the distance between the center of any three consecutive rivet’s,
and then divide by 2″
The following measurements may look different , but they interact, so you need to be aware of what guide bar you have fitted, or the type (size) of chain you have…
The Length of the Bar (this matches the number of drive links):
The length of the chainsaw bar is measured in two ways:
So Which Measurement do I Use?
For more detail, see the section below… ‘ Another Way of Finding What Parts You Need, The Chainsaw Chain & Guide Bar Markings: ‘
The Number of Drive Links in the Chain (this matches the guide bar length):
The number of drive links on a chainsaw, gives you the overall length of the chain. The drive links are the teeth on the underside of the chain. This number needs to match the drive link reference, often stamped on the chainsaw bar, or via the manufacturers reference table.
The guide bar mount (or ‘tail mount’) must fit the chainsaw body (head, or engine). The position of the guide bar fixings, oilway, and chain adjuster must line up with the those supplied on the chainsaw body.
There is no standard fitment (‘one size fits all’), so you may have to check any intended purchase via the suppliers fitment tables to ensure you get the correct fit. Many of the suppliers have a tool where you input your chainsaw make and model number to find the right guide bar.
As you can see below, there are numerous different guide bar mounts…
The images below show the chain sprocket cover removed, with the guide bar in position, and with it removed.
When replacing the guide bar, always clean the area to ensure the chain lubrication system and chain adjuster are able to work efficiently. And to ensure a good oil seal is made between the guide bar and its mount.
Don’t forget it’s important to ensure the guide bar and chain match each other. A slight difference in the specification (like the size of the gauge) can mean your chainsaw not working effectively and it’s very likely it will wear prematurely. In the worst case, incorrectly fitted parts can lead to safety issues, like broken chains, or taking risks (from frustration, because the saw won’t cut…).
Ordering Parts – Examples of what you can buy & how much they cost:
|Files & Guages||UK||https://ebay.us/NGHDiH|
If you look at the chainsaw guide bar, it will usually have a series of numbers stamped on it. This will give you most details about the bar and chain. The chain also often has a number stamped on the drive link that gives you details about the chain.
A typical paint worn chainsaw guide bar with the part numbers
(for reference, normally found near the engine end of the guide bar).
The markings illustrated above, reads as follows:
A typical series of chainsaw guide bar part numbers.
Each manufacturer may have a slightly different method:
Chains often have number(s) stamped on them. Using the manufacturer’s data, you can often use the number to find what chain you have fitted…
The reference code is often stamped on every other drive link…
Using this reference number, you can often find the exact chain you have, including the pitch, gauge, etc.
Example table of chain sizes and their reference numbers:
|Chainsaw – Chain Sizes|
|Pitch||Gauge||Chain Drive Link Ref No’s|
|1/4″||1.3||.050″||25||The detail can sometimes be inconsistent, or a different method may be used. Therefore please see the different manufacturer’s websites, or use your chainsaw guide bar part & reference numbers to obtain the correct fit.|
|1.6||.063″||16, 27, 59, 68|
Here’s a list of the most common chainsaw manufactures and parts suppliers (in no particular order):
– click or tap the image to view full size –