- If you can see daylight between the underside of the guide bar and the chain, it's too loose.
- If you can't move the chain around the bar, it's too tight.
- Make sure the chain brake is off and that you are wearing suitable work gloves.
- If necessary, slacken the nuts that are clamping the guide bar in place (or whatever system your saw uses to hold the side plate and bar on with). We don't need these really loose - just finger tight will do.
- Slacken off the tension until the chain is obviously too loose.
- Using one hand, hold the nose of the bar up.
- Now, whilst the bar nose up, adjust the tension so that the chain just touches the underside of the bar. Adjust the tension just a little bit more, so that the chain fits snugly against the guide bar - no need to overdo it.
- Whilst still holding the nose of the bar up, tighten up the side plate nuts / bolts / quick-release system.
- Ensure the nose sprocket turns!
- If your saw is a Husqvarna or Partner you may want to check the end of the guide bar and see if it needs greasing. Other makers may also put grease points for the nose sprocket so check yours - you'll see the rivets that hold the sprocket in-situ and off to one side will be a small hole. The Stihl bars tend to be sealed for life and therefore do not need to be greased.
- The teeth also wear, and instead of becoming dull and they wear down, they actually become very pointed. The teeth should have a slightly rounded point on them - if it's a sharp, triangular point then those teeth are worn too far.
- Is the bar straight?
- Does the sprocket at the end of the bar turn?
- Are the sprocket teeth worn?
- Are there signs of wear on the bar?
- Have burrs formed on the bar rails?
- Is there signs of overheating ("blueing" around the edges)?
- What condition are the bar rails in?
- Does the sprocket need greasing?
- Make and model of your saw.
- Length of your guide bar.
- The pitch and gauge of your chain.
- Stihl, MS260.
- 15" guide bar.
- Pitch 0.325" and 1.6mm gauge.
Continuing on our journey to achieving a sharp, effective chain, in this post we'll look at the depth gauges and find out one way of setting them. More after the jump...
- Inefficient cutting as you could be cutting deeper.
- Takes longer to carry out the task.
- ...you'll be trying to cut too much wood.
- ...vibration from the chainsaw increases dramatically.
- ...the saw may appear to be less powerful as it tries to keep up with the cut.
- But, worst of all, you massively increase the chance of kickback.
- You must only file depth gauges on the other side of the bar to you.
- You shouldn't file the depth gauge with the tool in place, otherwise you will effectively be altering the measurements set by using this tool.
Deciding Where To Start
- Chisel: Round Ground Chisel: Super
- Semi-chisel: Micro Chisel: Micro
- Chipper: Chipper: Standard
- What file size you should use.
- What filing angle you should be using.
- What the depth gauge setting should be (you do remember that the depth gauge on the cutter regulates how much wood gets cut don't you?)
- File size: 5.5mm round file.
- Depth gauge setting: 1.2mm (or 50 thou').
- Filing angle(1): we would need to hold the file 10o down, while...
- Sharpening angle: ...pulling it back 35o to ensure the correct cutting angle.
- Side plate angle: 85o. Forget about this for a moment - we'll deal with this in a later post.
- Cutter profile: this is the profile of our chain - notice Oregon don't call it a chisel, semi-chisel or chipper; this is also true of Stihl. All you need to be sure of is that the profile matches the chain you are holding (you are wearing gloves whilst you hold that chain aren't you?).
Husqvarna have made it very easy. Just take a look at the number on the drive link, look down the Husqvarna filing table for the same number and there you have it.
[HD VIDEO]: Sharpening The Chain
Determining Your Chain
- It must have the correct pitch.
- It must have the correct gauge.
- It must be the right length.
The pitch can be determined by measuring the distance between three rivets, then dividing this distance by two. Why three rivets? Well, because the rivets are not spaced equally around the chain and if you look closely at your chain you'll find that the spacing goes close, not-so-close, close, not-so-close, close... you get the picture.
There are common sizes for the gauge, interestingly (and I use the word in it's loosest sense) these measurements are often in metric, unlike pitch which is in imperial. Anyway, the common sizes are 1.1, 1.3, 1.5, 1.6, 1.8, 2.0mm.
- Cutter: this, as the name may suggest, cuts the timber - but it also regulates how much timber is cut.
- Tie-Strap and Rivets: these hold the components together and the chain gets its flexibility from the use of rivets, in the same way a bicycle chain does.
- Drive Link: this performs several functions as it transfers drive from the engine, cleans the guide bar groove as the chain rotates and carries the oil to lubricate the chain and bar. This link must match the bar in use as several different sizes of chain are available.
- The chisel profile is good for use in softwoods and it has a fast cutting action to slice through the timbers. This cutter profile is prone to dulling quickly and is therefore less durable than other types of cutter.
- At the other end of the extreme is the chipper profile, which is ideal for hardwoods, but has a slower cutting action. However, the advantage of this cutter is that it is more durable than the other types - and that potentially means less sharpening :-)
- In between these two types is the semi-chisel profile - this is a good all-rounder balancing the speed of cut of the chisel, with the durability of the chipper.
- Chain brake (manual / inertia) / left hand guard. This is really important - make sure that it works before you start to use your saw. The chain brake operates manually, but also reacts to the saw if it should kick back.
- Chain catcher. This small piece of plastic or soft metal sits close to the guide bar and chain under the side plate; if the chain should snap, or derail, the chain catcher takes the energy out of the chain, thus making it safer for you.
- On / off switch. Note which way the switch works to turn the saw off - they're not all the same - even the same manufacturer may use a different switch on different models. Stihl are pretty consistent about theirs - you need to move it upwards to switch off (which seems the wrong way round for me), but Husqvarna have changed from moving it the right to moving it downwards (which makes more sense).
- Safety throttle. Also known as a "Dead Man's Handle", but in these politically correct days that would be being 'dead-ist', so it's now a 'safety throttle'. Anyway, you need to press the lever in to operate the throttle.
- Rear hand guard. Used to protect your right hand, but also useful for stabilising the saw when you start it on the ground.
- Anti-vibration (AV) mounts. Fitted to saws to reduce the amount of vibration, which in turn reduces the chance of getting 'whitefinger' (Hand-Arm Vibration Syndrome).
- Exhaust. Directs fumes away from the operator
(unless the wind is blowing in your face).
- Scabbard (chain guard / 'condom'). This protects the chain, you and anything near the sharp end from getting damaged.
- Safety stickers. All saws must have safety stickers - it's a legal requirement here in the UK and they should warn you about the chance of kickback as well as pointing out that you really should have read the manual and be wearing proper protective equipment - they don't yet make chainsaw protective flip-flops and shorts.
- Chain type - bit odd this one, as it's the sharp pointy end, but the type of chain used can make it safer. More, lots more, on this one later.