Why does my chainsaw chain direction matter? What is the correct chainsaw chain direction?
This is common knowledge to folks who have owned and operated chainsaws, but newcomers often get confused with chain direction. Cutting teeth on a saw chain are designed to remove material in only one direction. So, by mounting the chain in reverse you will just generate a whole lot of smoke without doing any actual cutting.
By mounting a chain in the wrong direction, you can cause a lot of problems, such as:
- Crack/ burnout the clutch, because the chain will encounter increased resistance due to the blunt edge of cutters hitting wood instead of the sharp edge
- Put excessive stress on the guide bar, since the chain is being forced into wood by the weight of the user’s body instead of digging in by itself
- Waste bar oil
- Damage the chain links
- Look like a fool in front of your friends and family (and at the chainsaw dealer, when you tell him your brand- new saw isn’t cutting wood and he finds out you mounted the chain in reverse)
We created this article to clear up a lot of the general confusion surrounding chainsaw chains and their mounting direction. By reading this, you will learn how to avoid rookie mistakes and get the most out of your chainsaw.
VIDEO | Correct Chainsaw Chain Direction
When should you replace your chainsaw chain? | Tips and Advice
In order to ensure that your chainsaw is working as efficiently as possible, you need to keep it clean and well maintained. Sometimes you might have to replace certain parts. And there is no part on a chainsaw that is subjected to more abuse than the chain. Getting dragged through wood, dirt, and snow at speeds exceeding 90 feet/ s for hours on a daily basis does take its toll eventually.
Cutting wood with a dull chainsaw chain is an absolutely painful process, for it places unnatural levels of stress on both your body and the chainsaw. You have better chances of getting stuff done if you try to hammer a nail using a wet rag. The reason we made this article is so you can replace your chainsaw chain when it breaks or gets extremely dull. But first, you must be able to detect the symptoms of a busted chain.
The most obvious sign of a worn chain is when you feel the chainsaw isn’t cutting like it used to. The teeth get stuck in wood, logs that took 30 seconds to cut through now require twice as much time, and you struggle to force the chainsaw through wood because it isn’t pulling itself in. A sharp chain will dig into the wood, and you merely have to keep it stable with a firm grip. A dull chain will only generate smoke, without doing any useful work. You will have to force the chainsaw into the wood, and this can bend the bar or cause the engine to stall.
Another sign of a dull or worn out chain is fine sawdust. Normally, a sharp chainsaw chain will spit out chips of wood as it goes through the kerf. That is because the cutters aren’t slicing through the wood like a knife through butter, instead they are chipping away at the material like a hand plane. A dull chain doesn’t chip away wood, it merely scratches it (like sandpaper). So instead of coarse strands or chips of wood, you get fine sawdust and a whole lot of smoking and sparking because the chain is burning away the wood instead of cutting it.
If the chain is trying to run away in one direction as you make the cut, it is the sign of improper sharpening or a damaged guide bar. Maybe the cutting teeth are sharper on one side, or the guide bar rails are of uneven height which causes the chain to sit in a tilted position. Setting the depth gauge incorrectly will also mess with the performance of a chain. Every time you sharpen the cutters, you must also lower the depth gauge.
If you cut a whole lot of dirty wood, chances are you will strike a nail or rock at some point. This will break away one or more cutting teeth from your chainsaw chain, causing it to wobble in the middle of cuts and wear unevenly because centrifugal forces aren’t balanced across the chain. Sometimes, you might have to cut reclaimed lumber which is usually embedded with nails, dirt, etc. And when your chainsaw chain runs into a hard obstacle, it might not break a cutter tooth right away. Instead, what will happen is the chain links get bent out of their normal positions. Your chainsaw will keep cutting, but it is risky to operate for extended periods of time because the bent links can snap at any moment. The chain will also bounce around on the guide bar, instead of gliding over it smoothly.
Every time, before you set out to work on a project with your chainsaw, make sure to inspect the bar and chain thoroughly. Look for missing teeth, lack of tension, cracks or bends in the guide bar, etc. A chainsaw chain cannot be sharpened forever, it will eventually need to be replaced because every time you take away some material from the cutters during sharpening, they become smaller. There are witness marks on every cutter that act as a reference point, letting you know that the chain cannot be sharpened anymore and must be replaced.
Replacing the chain on your chainsaw | Procedure
Now that you know when to replace your chainsaw chain, let’s talk about the process of actually doing it. First, make sure you have access to a chainsaw scrench. This is a tool you must have in your pocket, or in a toolbox every time you go out with your chainsaw to cut wood. Bar nut sizes can vary depending on model and manufacturer, but a 19mm x 13mm wrench should be appropriate for most chainsaws.
Taking it apart:
When you’re ready to replace the chain, place the saw on a flat and stable surface like a table or workbench. On the field, you can use a tree stump or log of wood but be careful because even a stationary saw chain can cut your skin if you aren’t careful. Make sure you are wearing gloves if you are replacing the chainsaw chain outdoors on an uneven surface.
Now, take the scrench and using the proper socket loosen the bar nuts (don’t remove them just yet). A lot of screnches come with two separate hexagonal socket sizes- one for bar nuts, and the other for spark plugs. Most chainsaws have 2 bar nuts holding the clutch cover in place. Make sure to disengage the anti kickback chain brake before removing the clutch cover. After the bar nuts are loose enough to remove by hand and the chain brake is disengaged, locate the chain tensioning screw. It is going to be in one of three positions-
- On the side of the clutch cover, right between the two bar nuts
- In front of the clutch cover, on the outside edge of the guide bar
- On the crankcase, underneath the muffler and to the inside edge of the guide bar
Most modern chainsaws have side mounted tensioning screws (first configuration). This allows for the easiest access, and makes chain tensioning a much faster process. Once you’ve located the tensioning screw, take the screwdriver end of the scrench and loosen up the chain tension. This is going to come in handy later when you have removed the clutch cover and want to separate the bar from the powerhead.
So far, we’ve loosened the bar nuts, deactivated the anti kickback brake, and loosened the chain tension. Now, remove the clutch cover and place it aside. You have access to the guide bar and chain assembly, and the clutch drum should also be visible. Some chainsaws use inboard clutches while others use outboard clutches. Inboard clutches make it much easier to swap out drive sprockets. But let’s stay on topic for now, that is a discussion for another time. To remove the guide bar and chain, simply hold the tip of the bar and gently slide it forward and away from the powerhead. Then hold the rear end of the guide bar with your other hand and pull it out (it should be resting on two bar studs).
MOUNTING A NEW CHAIN IN THE CORRECT DIRECTION
Remove the old chain and put it aside. Take the new one and mount it onto the guide bar. This is the most important step, since we need to put the chain on the right way. See those cutters on the chain? The S- shaped links that have sharp, angled edges on the front and alternate between left, and right? Well, you have to make sure that the sharp edges of these cutters are pointing TOWARDS the nose of the bar on the top side, and AWAY from the nose of the bar on the bottom side. The nose of the bar is its front end, the one that has a sprocket and goes into wood. The read end has a cutout for mounting to bar studs, along with two oiler holes- one on each side of the bar.
Since the drive sprocket only spins clockwise in every chainsaw out there, the cutting edge of the teeth will move AWAY from you when they are on the top of the bar and TOWARDS you when they get around the nose and into the bottom side of the bar. Unclog the oiler holes and clear out the bar groove before reinstallation. Now, it is time to put the bar and chain assembly back on the saw. Make sure that the chain sits right on top of the drive sprocket (it is next to the clutch drum) when you put the bar back in. Seat the rear end of bar on top of the bolts, and make sure to align the tensioning pin with the hole on the bar.
Reassembly and chain tension
Take the clutch cover and align it properly with the bar studs and tensioning pin. Now hand tighten the bar nuts, because we must first tension the chain before fully securing the clutch cover to our chainsaw with the scrench. Hold the bar by the nose and lift it up slightly. Look for slack in the bottom end, if the chain is hanging off the bar rails at the bottom, take the screwdriver side of the scrench and adjust the tensioning screw until you can’t see any light passing between the chain and the bar.
To test chain tension, hold the chain in the middle section of the bar with two fingers and give it a slight tug. It shouldn’t move more than ½” away from the bar, snapping right back into the bar groove. Too loose, and the chain will derail. Too tight, and you will burn out both the chain and the bar.
Finally, it is time to properly screw in the bar nuts using the scrench which will secure the clutch cover. Give everything a visual inspection, looking out for cracks or dents in the bar and chain. Now your chainsaw is ready to cut wood.
How to find the correct replacement chain for your chainsaw?
There are three parameters you need to consider before purchasing a new chainsaw chain-
- Pitch: This is the distance between any three consecutive rivets on the chain, divided by 2. Basically, it is the average distance between any 2 consecutive chain links and a larger pitch generally means a heavier and bigger saw. The most common chainsaw chain pitch values are- ¼”, 0.325”, 3/8”, 3/8” low profile (Pico), and 0.404”.
- Gauge: This is a measure of how wide the groove is on a guide bar. The chain rides on drive links that sink in between the rails of the bar, and they must fit snugly in here to reduce wobble and provide stability at high speeds. Gauge also refers to the thickness of drive links. Higher gauge means heavier duty chain, designed for more demanding applications (industrial, rescue, military, etc.). The most common gauge sizes are- 0.043”, 0.050”, 0.058”, and 0.063”.
- Drive link count: As you might have guessed, this is the number of drive links on a saw chain. Drive link count gives you an indication of how “long” the chain is and whether it will fit around a guide bar.
All of this information is printed on the box that the chain comes in, and some models even have pitch, gauge, etc. stamped into the drive links of the chain. Let’s say you lost the box; now how do you tell the store assistant what type of chain you need? At least when it comes to drive links, you can remove the chain and count it yourself. But gauge and pitch are hard to measure accurately without specialized tools (like digital calipers). But you don’t have to spend big bucks on a fancy digital caliper. The Oregon 556418 Bar and Chain is an extremely handy pocket- tool which measures chain pitch, gauge, and will also help you clean the bar groove. It will even measure the round file size (for when you need to manually sharpen a chain).