What is Chain Pitch?
Chain pitch is the distance between any three consecutive rivets divided by two. Pitch defines the size of the chain. OREGON® chain is made in several pitches - 1/4" is the smallest, 3/8" is the most popular. Other parts of the cutting elements are pitch-related. The drive sprocket must be the same pitch as the chain, and so must the nose sprocket in sprocket-nose bars.
- What is Chain Gauge?
Chain Gauge is the Drive Link's thickness where it fits into the guide-bar groove. The gauge of the chain and the gauge of the guide bar must match. OREGON® has several gauges - such as .050", .063", etc.
How do I measure the length of my chain?
The length of your chain is determined by counting the number of drive links. Common examples are 70 for "D" or "72" chain and 56 for "S" or "91" chain.
- How Tightly Should I Tension My Chain?
For a sprocket nose bar, turn your saw's tension-adjustment screw until the bottoms of the lowest tie straps and cutters come up and contact the bottom of the bar rails, then turn your tension-adjustment screw an additional 1/4 turn. Also, on sprocket nose bars, the snap test should be performed. Grasp the chain along the bottom of the bar, pull down, and let go. The chain should snap back to its original position, solidly contacting the bottom of the bar rail.
For a solid-nose bar, turn your saw's tension-adjustment screw until the bottoms of the lowest tie straps and cutters come up and contact the bottom of the bar rails. Chain tension on a solid-nose bar should be adjusted looser than on sprocket nose bars.
Regardless of your bar type, your chain should move freely around the bar. NEVER TENSION CUTTING CHAIN WHILE IT'S HOT!
OREGON® has just introduced the new Intenz® guide-bar chain tensioning system. See:
- How Often and What Type of Lubrication Should I Use in My Saw?
Keep your saw's chain-oiling system filled with clean bar-and-chain oil. Never put used oil, or old motor oil, in your saw or on your chain. Be sure your chain, bar, and sprocket are always receiving oil from the saw during operation. Fill your oil reservoir each time you fill your gas tank.
- Why Would My Chain Pull or Cut to One Side?
Several things can make a chain cut crooked, or pull to one side. The following are the causes and the remedies:
Uneven top plates can cause a chain to cut crooked. It's important to keep all top plates equal length.
Dull cutters damaged by rocks can cause a chain to cut crooked. It's important to remove all damage from cutters prior to cutting. Cutting with a dull chain can accelerate wear to the bar and chain.
Different depth gauge settings from left to right. Keep all depth gauge settings equal from left to right.
Different top-plate angles from left to right. If you sharpen your chain at a 25° setting on your left hand, your right hand cutters should match.
A worn guide bar. A badly worn bar cannot be repaired. If your system is cutting crooked and you have narrowed it down to the bar, more than likely the rails, or the inside of the bar, are damaged beyond repair.
- How Do I Know When My Chain is Dull, and When Should I Sharpen?
Keep in mind that a sharp chain will cut large-size chips. A chain that is dull or has abrasive damage will create sawdust. It's time to sharpen when you're having to push on the saw or the saw is no longer self-feeding.
How Do I Sharpen My Chain?
Always inspect your chain prior to sharpening. Check for the following:
- Bent or burred drive links
- Broken cutters or tie-straps
- Loose rivets, broken rivet heads
If broken parts are detected, take it to a servicing dealer for replacement of parts or replace the entire chain. The following steps will help you correctly sharpen (with a round file) OREGON® saw chain:
When hand filing it's important that 1/5, or 20 percent, of the file's diameter is always held above the cutter's top plate. Using the correct file guide is the easiest way to hold the file in this position.
Keep the correct top-plate filing angle line on your file guide parallel with the chain. Many cutters have a guide mark stamped near the rear edge of the top plate that can also be used as a guide for filing angle.
Sharpen cutters on one side of the chain first. File from the inside of each cutter to the outside. Then turn your saw around and repeat the process for cutters on the other side of the chain.
If damage is present on the chrome surface of top plates or side plates, file back until such damage is removed.
Keep all cutters equal. Start with the cutter with the most damage and hand file all cutters back equally.
Note: Do not file or alter the tops of kickback-reducing bumper tie straps or bumper-drive links, except on 33SL, 34SL and 35SL chains. Only on 33SL, 34SL, and 35SL will the bumper tie straps be filed down while the cutter depth gauges are filed.
- How Do I Set My Depth Gauges?
Prior to setting your depth gauges it's important to have the correct depth gauge tool. Most OREGON® chains have a number stamped on each cutter located on the depth gauge indicating the correct depth gauge setting. If unsure of your OREGON® chains depth gauge setting, ask your OREGON® saw chain dealer. The following steps will help you correctly set your depth gauges:
Use a depth-gauge tool with the correct built-in setting for your chain and check your depth gauges after every third or fourth sharpening.
Place the tool on top of your chain so one depth gauge protrudes through the slot in the tool.
If the depth gauge extends above the slot, file the depth gauge down level with the top of the tool using a flat file. Never file the depth gauge down enough to exceed the depth gauge setting specified.
Note: Do not attempt to file or alter tops of kickback-reducing bumper tie straps or bumper drive links, except on 33SL, 34SL, and 35SL chains. Only on 33SL, 34SL, and 35SL will the bumper tie straps be filed down while the cutter depth gauges are filed.
- How Can I Get OREGON® Literature?
Should I Do Anything Special With a New Chain?
Yes. Taking these few simple steps prior to using it can extend the life of your new chain:
If possible, soak the chain in oil to allow oil to penetrate all chain components.
Never run any chain on an over-worn drive sprocket, especially a new chain. Replace drive sprocket system after every two chains, or sooner.
Adjust chain (see chain tension)
Run new chain at half throttle for several minutes before doing any cutting; this allows oil to reach all parts of the bar and chain. Let sprocket, bar and chain warm up fully.
Stop the motor, let the chain cool, then check and adjust tension.
Keep the first several cuts light. Keep extra oil on the bar and chain during these first cuts, and do not apply heavy pressure. Check chain tension often during the first half hour of use.