Chainsaw Guide Bar Inspection - Maintenance

This page contains a down and dirty reference for your chainsaw guide bar inspection and preventative maintenance.  In the chainsaw world, there's plenty of opinions as to how this practice should occur - this is one interpretation.  Guide Bars receive a ton of abuse, they're expensive and an integral part of operational safety and performance.  A quick tip... if you happen pinch your bar, use a wedge and felling axe to relieve the strain (when bucking).  If you overly torque on the bar, you will bend it - causing your saw to cut crooked (if your chain sharpening skills lack, you'll exacerbate the situation).  Follow the slide-show and written regimen below to learn more about bar inspection, and preventative maintenance.

  1. Remove, clean, and inspect your guide bar tip, base, rail, and heel.  Inspect for wear on the inner/ outer rails and the bar itself.  Use a tool to scrape out the sawdust and oil from the inner bar rail groove (See Image 3), ensuring to unclog the bars oil port (See Image 2).  Gunsight the bar for unevenness or bends (See Image 4).  Inspect the bar tip sprocket for roll-ability and wear (See Image 1). 
  2. If the bars rail has developed burs or mushrooming (depending on the severity, you may need to junk the bar), remove the condition with a fine - flat file, dry stone, or 250+ grit sandpaper (See Image 6).  Bottom line, if you're taking a flat file to your bar, you may need to increase your maintenance intervals.  Tip: carry sand paper in your saw kit to address the start of any burs, while performing field maintenance.  Loose chain tension will wear your bar groove and rails - causing the chainsaw to cut crooked.  Rotate your bar after every sharpening - this will extend bar life.
  3. If your chainsaw guide bar has a unplugged hole (used when manufacturing guide bar) , clean the sawdust from the hole and replug.  Your local dealer should have plugs for sale (See Image 8).  A plugged bar hole will cause the bar to stick while cutting.
  4. Re-assemble your bar and chain to its powerhead, remembering to rotate the bar for even wear.  Adjust your chain tension properly and inspect for chain drift (See Image 7).  Take a straight edge perpendicular to your saw bar and outer chain tooth (image 5).  If there's clearance between the bar and tooth, then (most likely), your inner bar rail has not worn, and doesn't need replacing.  If you're able to move the chain tooth (i.e. the chain will rest flat against the straight edge), it's a good indicator that your inside rail groove is worn.  If you can rescue your removable tip, do so and junk the bar.  Tip.  Frequently inspect your chain tension to prevent chain throw, chain driver/ inner bar rail damage, and clutch/ sprocket wear.  Getting a good start on preventative saw maintenance will save you time, money, frustration and increase your operational performance.  ​For more information on chainsaw guide bar, chain sharpening, or my other valuable services, please contact me.