Chain Sharpening: Part 1...

Sharpening your chain is one of those necessary evils that we all have to do in order to keep the chainsaw cutting efficiently, a dull, worn cutter is just not effective at getting through the wood and it'll tire you out, making life harder.

So, for an easy life with your chainsaw it's worth learning the art of sharpening the chain - it'll save you having to take the chain to your local garden machinery centre to have it sharpened and that means saving you money. How's that then, this site is already making your like easier and saving you money.

In order to sharpen your chain though, there's a few things that you need to know first - find out more after the jump.

To maintain your chain at it's most efficient and effective, you need to know something about your chain to find out the following details...

• 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?)

To do this you have to know how to identify your chain, then you can set about finding the information you need. Let's take a look at chain ident.

Chain Identification

If you click on the image at the top left of this post, you'll see that the chain has some numbers on it (this particular chain is made by Oregon - one of the largest producers of after-market equipment for chainsaws).

The numbers appear on both the drive link and the cutter - or more specifically the depth gauge on the cutter. These numbers give us some clues to the chains identity - but be warned... Oregon, Stihl and Husqvarna all mark their chains differently, the numbers may be in the same place but the meanings differ. So here's your simple guide around the murky world of chain identification.

Oregon

Looking at that image again we can see that on the drive link is the number '18' and on the depth gauge, '50' appears. With Oregon chains the number appearing on the drive link is an I.D. number that you can cross-reference with a filing table.

The image above shows an Oregon filing table, these are pretty easy to use and your first step is to take a look down the left hand side and find the row which relates to the number of your chain.

Our particular example shows a number '18' chain - look down the bottom of the table and you'll find a row marked '18H*'; that's ours. Reading across the row, we find the following information (L-R):

• File size: 5.5mm round file.
• Depth gauge setting: 1.2mm (or 50 thou').
• Filing angle(1): we would need to hold the file 10^o down, while...
• Sharpening angle: ...pulling it back 35^o to ensure the correct cutting angle.
• Side plate angle: 85^o. 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?).

But what if you have a #21 or #22 chain? Looking down the left hand column shows that there are two rows with these I.D. numbers - and the information within those rows is different. So how do you choose which one is yours? Easy - look over at the right hand side at the profile pictures, compare it to your cutter profile and whichever one matches is your row.

Stihl

Stihl do things differently, and the numbers on the chain refer to different things compared to Oregon (and Husqvarna). It's not better or worse, just different.

The number on the drive link of a Stihl chain relates to the gauge of that chain and you'll see one of the following:

1, 3, 5, 6, 8, 0

These figures relate to the normal gauge sizes of:

1.1, 1.3, 1.5, 1.6, 1.8, 2.0mm

The number on the cutter shows the pitch of the chain and will be listed as:

325, 3/8 or 404

We can use this pitch information to find the data we need for sharpening the chain; just search for all the chains with your pitch and refer to the chain type. We'll cover this in more detail in another post, as Stihl refer to their chains as Rapid, Picco, Super, Micro and Standard.

Husqvarna

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.

Simple.

Next post... we'll take a look at the naming convention used by different manufacturers for their chain.

Related Posts:

[HD VIDEO]: Sharpening The Chain

Pitch And Gauge...

The chain has got to be one of the most important things that you'll purchase for your saw on a regular basis; it's designed to fit around the guide bar, and it's important to get the correct chain for your bar / saw. There are three basic considerations to get right when purchasing a new chain:

Find out more about these considerations after the jump.

Determining Your Chain

1. It must have the correct pitch.


2. It must have the correct gauge.


3. It must be the right length.

Pitch

As with a bicycle chain, the chain itself must fit around a couple of sprockets - one by the pedal, and one on the wheel; fortunately you don't have to pedal a chainsaw but there are still two sprockets that our chain must fit. The pitch of the sprocket must be the same as the pitch of the chain.

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.

Fortunately there are standard sizes of pitch: 1/4", 0.325", 3/8" and 0.404" and you can either measure it, look at the box your original chain came in (you did keep that, right?) or look on the side of the guide bar as it's often etched in there.

Gauge

The second important measurement when it comes to ensuring we get the right chain is the gauge - this is the thickness of the drive link and it's got to be the right size to fit in the groove of the guide bar.

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.

Chain Length

The length of the chain is obviously critically important too, but what is surprising is that just knowing the length of the guide bar is often not enough to ensure the right chain. This is because an 18" bar on a Stihl requires a different length chain to an 18" bar on a Husqvarna, so a better system was needed to ensure the correct length.

The length of a chain is properly determined by the number of drive links, this is often etched on the side of the guide bar - or you can sit there and count them (just remember which one you started counting at).

Chain components...

The chain you use for sawing will be made up of just a few components - but those components have a bearing on what the chain will be best suited to, and how safe it is.

Although there are many different types of chain, made for particular applications such as rip-cutting, cross-cutting, metal cutting, chains (for the moment at least) can be divided in to standard chains and safety chains.

A standard chain has the following components:

• 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 components above form a standard chain, but there is an additional chain component that can add to the safety of this item by smoothing out the cutting action, reducing vibration (and therefore whitefinger) and reducing the chance of kickback. This component is called a Guard Link and is really a modified drive link. This link has a sloping top, and it's position in front of and alongside the cutter helps the lift the wood up to the cutting edge.

Cutters come in a variety of profiles, which are best suited to particular applications and each has it's own advantage and disadvantage.

• 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.

Next post... pitch and gauge.