Chain Saws, Part 2. Maintenance A Master Class

Chain Saws Part 2 Maintenance

There will be two weeks on this topic. It is just too big to put all the information in one blog post.

As homesteaders, we tend to use our chainsaws year-round, compared to the general homeowner who runs it mostly in the fall. The saw in the intro picture was used to cut a cord of firewood and is now ready for clean-up and maintenance.

I recommend all saw operators to watch a safety operation video from Stihl on YouTube. The video is 1.03 hours long. I show it to all my classes. The video is called “Stihl Safety, Operation and Maintenance.” www.youtube.com/watch?v=Cw6f9dfCuNM

The video is very good but it glosses over some important points, which I will attempt to bring to your attention. We will be covering only gas power saws in this session.

In the video, you are told to clean and prep your saw when you come in from the woods at night. When I come in, I’m tired. If I had the energy to clean and prep a saw, I would still be in the woods, cutting wood. I tend to clean and prep the saw when I am refreshed and organizing to go work. The only exception is when I am putting the saw away for a while and want to prep it for long term storage.

I am breaking down this topic by parts of the saw requiring maintenance. This will make it easier to cover and I’m sure not to miss anything.

NOTE: When doing saw maintenance, you should always wear safety glasses and gloves.

1. When buying a chain saw, consider these points:

a. Is there local service for repairs?

b. Do you have to buy on-line only and not at a brick and block store?

c. How fast can you get the saw?

d. How well does this saw work for me?

e. Can you sharpen it?

f. Can you make repairs?

g. Have you talked to others who have experience using the saw you are buying?

h. What is the final cost – saw purchase parts and repair parts?

2. When you buy your second saw, consider getting one that will have interchangeable parts (chains, bars, sprockets) with the saw you already own, or if you have 3 or more saws, you only want to have to keep 2 sizes of replacement / repair part sizes and gauges. You want to be able to mix and match chains and bars.

3. The chain brand that I use allows me to cut up to 3 cords with a new chain and then, after sharpening, I can cut at least 1 ½ cords before sharpening again.

4. Air cleaner and carburetor compartment

a. The air cleaner needs cleaned daily. There are plastic/nylon filters or paper/fiber filters

b. Use a brush to remove saw dust

c. Use forced air (air hose) only on plastic type filters, never on the paper/fiber ones.

d. Replace fiber filters when you replace the sprocket

e. Replace spark plug once a year or when you replace the sprocket

f. Never use sandpaper to clean the spark plug because sand particles will destroy the aluminum engine

g. With the filter off, cover the carburetor throat with rags, tissue, or tape.

h. Use forced air pressure to blow the dust out of the area

i. Also use the air hose to blow dirt and trash out from the flywheel fins, under the recoil housing.

j. Replace air filter properly and the top cover of the saw

bar stud and nuts with side cover

5. Cleaning the sprocket, bar, chain, and side cover

a. Make sure the chain break is off – not in locked position

i. Removing the side cover with the chain brake engaged causes damage and a costly trip to a saw dealer.

b. Use a permanent magic marker and mark the top and bottom of the bar. This will save time later.

c. Loosen the bar stud nuts and reduce the bar tension screw

d. Wear gloves due to the sharp cutting teeth and metal slicers from the bar chain

e. Remove the bar and chain, keeping the bar nuts in a safe place

f. Under the side cover, remove the dirt and trash with either a brush or the air hose

g. Make sure to clean the oil slot on the saw that lubricates the bar and chain

h. Check the sprocket, it should be replaced when you wear out two chains OR have replaced the bar

i. Most sprockets are easily replaced by removing the circular clip pin

ii. When replacing the sprocket, grease the shaft and snap the clip pin into place

iii. Some brands/models of saw require the dealer to use a special tool to do this service

iv. There are different designs for sprockets. I prefer the rim sprocket

6. Bar Maintenance

a. Be aware that different saw brands and models have different designs for the chain tension screw – therefore, not all bars are interchangeable even though they are the same length

b. Bar grooves are also various widths – called gauges – and chains, bars, and sprockets must match

c. When buying replacement bars, chains and sprockets, attempt to standardize all your saws

top bar is replaceable power tip, bottom bar sprocket nose tip

d. There are 3 major styles of saw bars

i. One-piece solid nose bars

1. They are cheaper, but the chainsaw tension has to be run loosely, allowing chains to jump off the bar more often

ii. The sprocket-tip, laminated bar

2. This bar allows tighter chain tension and the sprocket aids in the chain performance

iii. The laminated replacement sprocket tip bar

1. A premium bar that costs more but the tip can be replaced

(Both the sprocket tip and replacement power tip bar run faster than the hardnose bars however, the sprocket does break down. I can replace a sprocket tip bar and chain for a 20” bar for $32.00 whereas the replacement sprocket tip power bar alone – no chain – costs over $57.00.)

iv. Most bars become damaged and wear out due to operator misuse

v. Replacement power sprocket tip bars require experience and tools to make the repairs

vi. Remember, chainsaw bars can be bent and broken. DON’T use the bar as a pry-bar

vii. If the bar groove gets pinched, you can buy or adapt a tool to open the bar groove again.

bar groove ready to be cleaned

e. The bar groove will need to be cleaned of built-up oil and saw dust. You can buy a bar groove pick or use a putty knife to remove the build-up on both top and bottom of the bar. I like to finish cleaning the grooves by using an air hose.

f. The bar has slots for chain tension adjustment and slots for lubricating the bar. Be sure the clean these areas

g. Failure to remove the dirt build-up in the bar will cause the chain drive links to ride up and out of the bar, throwing the chain off the bar

h. If the saw chain jumps off the bar, the drive links may be damaged or burrs will form on the drive links. They need to be filed off before replacing the chain back onto the bar

i. The way the saw chain performs is that as the chain is rotating around the bar, the cutting teeth rocks back on its heel and pushes upward into the wood fiber. Then, it rockets back to the bar rail and continues this process around the bar

i. The constant action of the chain hammering back down on the bar causes the bar rails to mushroom outward at the top groove edges

bar tip with mushroom burr needs filed back (enlarge the picture on your screen)

ii. The mushroom burrs on top of the bar rails need to be filed back down to the original bar width. If the burrs aren’t removed the bar width becomes wider than the chain cutters

j. The bar tip sprocket should be lubricated daily when the saw is in use, at the tip if the sprocket has a grease hole

7. Saw chain is a crap-shoot of options

a. There is ¼”, 0.325”, low profile 3/8”, 3/8” chain, chipper angle, semi-chisel angle, chisel angle and safety anti-kickback chains also have various drive link thickness (gauge). We haven’t even begun to discuss lengths

b. The chain size needs to match the bar groove size (gauge) as well as the sprocket

c. Saw chain grade comes in all grades of hardness

i. Soft-grade chains are easy to sharpen but don’t hold the cutting edge for a long period of time

ii. Hard-grade chain can cut a lot more wood than a soft chain before it needs sharpened. However, it takes more experience to sharpen and sometimes requires special tools or files to do so

iii. Soft saw chains, 16”, can cost as little as $8.00 and specialized hard diamond tip 16” chains can cost over $1000.00

iv. I prefer to pay more for a chain that requires less sharpening—Not $1000.00 though

v. I recommend you visit and review a site - Chain Saw Direct (www.chainsawdirect.com) to learn more about bar and saw chains

vi. Another site is from Oregon chain saw company – Technical tips, chainsaw bar maintenance (https://www.youtube.com/watch?v=EcwQJNwckTo) There is a series of videos available that are helpful. Most of them are fairly short, too.

d. If you have more than one saw, try to have them so you are able to interchange chains, bars and sprockets. However most smaller saws use .325 chain, therefore you may have to have two bar, sprocket and chain sizes

e. For inexperience saw operators, anti-kickback saw chain is recommended, it doesn’t totally stop kickbacks but reduces the potential number of kickbacks

f. Saw chains need to be sharpened to maintain a sharp cutting edge

g. Saw chain dull quickly when it hits the ground, metal and rocks

h. The top of the cutting tooth is chrome plated, if that chrome is scraped off or broken on the cutting edge; the chain will need to be sharpened back to the chrome plating, otherwise the chain will not hold a cutting edge

i. Saw chaining sharpening

i. Each saw chain size uses different sizes of round files

ii. Semi-chisel, chisel and chipper chains require different filing methods

iii. When cutting, occasionally touching up the cutting tooth with 3 stokes of the file will help to keep a sharp chain

iv. Always file the chain from inside towards the outside edge

v. Always file the chain with the same number and even pressured full strokes, maintaining the same angle for each stroke

vi. Each brand of chains has a different cutting tooth angle, the important thing when sharpening is to maintain all cutting teeth at the same angle

vii. There are many types of sharpening tools available, the key to their success is the operator’s skill

viii. A good idea, if you file by hand, is to occasionally have the chain sharpen by machine to maintain each tooth’s angle and length

ix. Find an old saw chain and practice your sharpening skills before filing your good chains

x. On the front of the cutting tooth are rakers /depth gauges

xi. The depth gauges determine the amount of material the cutting tooth removes on each cut

xii. As the cutting tooth is filed back the depth gauge needs to be filed down so as to maintain a maximum cutting performance

xiii. The depth gauge should be set at .025 of an inch, check every 3 or 4 filings

xiv. Improper chain sharpening and bar rail burrs can result in poor saw performance such as cutting moon cuts, making saw dust instead of wood chips and kickbacks

notice the lettering on the bar is upside down, bar is rotated to ensure even wear

8. Reassemble the bar and chain

a. When reassembling the bar rotate the bar so as to extend its life, that’s why you marked the bar when you took it off, putting the ‘top’ at the bottom and the ‘bottom’ at the top. This ensures even wear and tear.

b. Place the chain on the bar, make sure it rotates smoothly around the bar

c. Next place chain around sprocket and then insert the bar over the bar studs

cutting teeth are pointed in the correct direction - the end of the bar

d. Important, the chain cutting teeth has to be pointed on the top of the bar out towards the tip away from the saw handle

e. If you aren’t sure look on-line to make sure it is correct, the chain will not cut if it’s put on backwards

f. I have been to box stores, and even some saw shops, where the chains are put on backward

g. As you place the bar over the bar studs adjust the chain tension screws to tighten the chain on the bar

h. Make sure the chain is in the sprocket correctly

tension screw on side-mounted cover

i. Some saws have the tension screw built into the cover plate

j. Place the side cover over the bar studs and hand tighten the bar nuts

k. If everything is in place, continue to tighten the chain tension screw

l. Check the chain by rotating the chain around the bar by hand, if it is loose, tighten the chain, if it pulls hard loose the tension

m. Important – ALWAYS—Tighten the backbar stud nut first, then the front nut and retighten both again. If you tighten the front nut first the bar nuts will vibrate loose

n. Place some bar oil on top of the chain, on a new chain add addition oil to lubricate the bar and chain

o. To check proper chain tension, start the saw, the chain should rotate feely around the bar, when you remove your finger from the gas trigger the chain should stop within 2 to 3 seconds. If the chain is still rotating, even slowly, shut off the saw and tighten the tension

p. Don’t over tighten the screw, it will bend or break

q. Also only adjust the chain tension when the bar nuts are loose

r. Common Sense---Never check the chain tension by hand unless the saw is shutoff, don’t trust the chain break with the engine on

There is so much more to learn about chain saw maintenance. Use your online and saw dealer resources to educate yourself about your saw. A good maintenance technician is worth his/her weight in gold.

Remember a chain saw is just a tool, but it can be very dangerous if not maintained properly.

Next time we will cover fuel and lubrication for the saw.

Until then, Happy Cutting,

Bob