A Guide to Safety with Chainsaws
Care of Your Chain
In many ways the chain is the most important part of your chainsaw. It is the part that needs the most attention but fortunately maintenance is not too difficult for the average user.
Dangerous Chain Conditions
Any of the following conditions can increase a chain's potential kickback energy or increase the hazards to the operator:
- Incorrect sharpening angles of the chain.
- Excessive or incorrect depth of gauge settings.
- Loose chain tension.
- A dull chain.
- Any alteration to kickback-reducing features.
Four Rules for Chains
There are four basic rules to ensure that your chainsaw chain performs safely and well.
Keep the chain:
- Well oiled;
- Correctly tensioned;
- Sharp, with correct cutter angles; and
- The depth gauge height to the 'cutter' is correct.
Oiling
A constant supply of oil to your chainsaw's guide bar, chain and sprocket is essential to prevent excessive friction wear and damage.
Regularly check that the chain oiling system is working.
Always use chain lubricating oil or oil recommended by the manufacturer. Never use waste or used oils - these contain impurities that can damage the chain, and the oil mists thrown off the chain can cause health problems.
Tensioning
Loose chains can affect the depth gauge effectiveness and result in greater kickback potential and increased guide bar and sprocket wear. It may also cause the chain to jump off the guide bar.
The chain should be tensioned so that it is touching the whole way around the guide bar. The chain should fit snugly but still be easily pulled forwards from the chainsaw body towards the guide bar tip.
Fig 25: Regularly check chain tension and correct as necessary.
Tension the chain before each use. Tension the chain often, or at each refuelling.
Never tension your chain right after cutting.
A chain tensioned while hot can cool and shrink, causing tension to be too tight. Let the chain cool first.
Always wear protective gloves.
Follow these steps:
- Turn the engine off.
- Loosen bar-mounting nuts on the side of your chainsaw.
Fig 26: Loosening the bar-mounting nuts
- Adjust tension as follows:
(a) If you have a solid-nose bar
Pull the bar nose up and keep it up as you adjust tension.
Fig 27: Pulling the bar nose up
Turn your chainsaw's tension adjustment screw until the bottoms of the lowest tie straps and cutters come up and just touch the bottom of the bar rail.
Fig 28: Adjusting the tension so the straps and cutters just touch the bar rail
While still holding the nose up, tighten your chainsaw's rear bar-mounting nut first, then tighten the front mounting nut.
(b) If you have a standard sprocket-nose bar
Pull the bar nose up, and keep it up as you adjust tension.
Fig 29: Pulling the bar nose up
Tension must be tighter on a sprocket-nose bar than on a solid-nose bar. Turn your chainsaw's tension-adjustment screw until the bottoms of the lowest tie straps and cutters come up and solidly contact the bottom of the bar rail. Then add an additional quarter-turn of the adjustment screw.
Fig 30: Adjusting the tension so the straps and cutters solidly contact the bar rail
While still holding the nose up, tighten your chainsaw's rear bar-mounting nut first, then tighten the front mounting nut.
(c) If you have an Intenz™ sprocket-nose bar
Turn the tension-adjust slot until the bottoms of the lowest cutters and tie straps come up and solidly contact the bottom of the bar rail.
Fig 31: Adjusting the tension so the straps and cutters solidly contact the bar rail
Tighten your chainsaw's rear bar-mounting nut first, then tighten the front mounting nut. It is not necessary to hold the nose up when adjusting tension on Intenz™ bars.
Note: When replacing a standard bar with an Intenz™ bar, the chainsaw's adjustment pin must be removed. Contact your dealer if you need help.
Fig 32: Remove the adjustment pin
Pull the chain by hand along the top of the bar several times, from the engine to the bar's tip. The chain should feel snug but still pull freely.
If you have a sprocket-nose bar, you should now perform the snap test. Grasp the chain along the bottom of the bar, pull down, and let go. Chain should snap back to its original position, solidly contacting the bottom of the bar.
Check tension often during operation, especially during the first half hour. If the chain loosens: stop, let the chain cool, and readjust tension.
Sharpening
When it is sharp, with correct cutter angles maintained, your chain does the work.
If not, you do the work, safe working conditions are reduced and excessive chain wear can result.
Let's look at the parts of a cutter.
Fig 33: The parts of a cutter.
There is a range of angles for cutters, which are illustrated below.
Fig 34: There is a range of angles for cutters.
You should sharpen your chain to the manufacturer's recommendations for your particular chain. The basic tools you need are a round file with handle and a file guide, which you can buy from your chainsaw dealer.
Fig 35: Basic tools are a round file and a file guide.
All cutters should be kept to an equal length and shape for the life of the chain. Use the correct file guide to ensure the file is held at the proper depth and angle. Do not use a file without a handle.
Fig 36: Use the correct file guide to ensure the file is held at the proper depth and angle.
File from the inside out with smooth strokes of the file, using the file guide to maintain the correct angle.
Sharpen cutters on one side of the chain first and repeat for the other side. If cutters are damaged, repair by filing them back to correct shape or replace if necessary. File replaced cutters back to the same length as the rest.
Fig 37: Use the file guide to maintain correct angle.
Depth Gauge Setting
The depth gauge controls the thickness of the chip the cutter will remove. Their proper maintenance is essential for good performance and safety.
Basic tools are a flat file and the correct depth gauge tool as recommended by the manufacturer.
Fig 38: Use a flat file and correct depth gauge tool.
Place the depth gauge tool in position and file from the inside of the cutter outwards.
After lowering depth gauges, file off the leading edge and maintain the original shape of the depth gauge.
Check depth gauges after 4-5 sharpenings.
Note: When you have to replace the chain on your chainsaw, replace the sprocket as well.
Fig 39: File from the inside of the cutter outwards.
Fig 40: Maintain original shape of the depth gauge.
