Chainsaw Repair

Grinding your saw's bar to keep it cutting straight and vastly extend it's life is something people overlook. As a mechanic in a shop it's a job I would perform at any tune-up or servicing of any saw. Keeping the rails of the bar true will keep if from wearing faster and only takes minutes to do. If you have access to a tablesaw you only need to purchase a $10 metal cutting disc from a hardware store( 7" diameter,1/8" thick with a 5/8" hole),then you will be able to grind and true all the bars you want for many years,and probably not need to buy new bars anymore.

Install the metal cutting disc in the tablesaw,then using a square adjust the disc so it is exactly 90 degrees(lining up with the square),using the adjustment wheel on the side of the tablesaw. Put on a safety face-shield and leather gloves and start the tablesaw,now you want to be grinding the bar about 1-2 inches from the outside edge of the disc,you can see by where the sparks are. First pass grind lightly starting where the bartip meets the bar, then slowly and steadily push the bar all the way through all the way and around the "tail" of the bar,then do the other side. Now inspect each side of the bar and you will immediately see where all the most wear is. Now make more passes until you've ground the worn areas away and the rails are now,flat,square and true. Clean the grooves and blow them out with air and grease the tip,good as new.
Warning- You only need to exert light pressure to grind the bar,but it is possible for someone to push the bar very hard into the disc causing it to break and fly apart. I've been doing it for 20 years without a problem,but for extra safety you can make a steel or aluminum disc to fit behind the cutting disc for extra safety,even a smaller diameter saw blade behind it would work.
Saw shops charge $10 to $20 to grind a bar,and many of them are not set accurately at 90 degrees ever,so not always very accurate or true.
Bars can be ground over and over many times,a real money saver for people running long expensive bars.

I would give the customer a receipt disclaiming your liability if they injure themselves and have them sign it, if something about the machine is unsafe.

The grinding disc I have now I bought about 20 years ago,it's still in great shape,it's paid for itself a hundred times at least $$,now that I'm retired I service all my friends bars with it in exchange for favors.
I'm guessing a lot of saw shops today do not have a bar grinder,better to sell a $100 bar than make $10 grinding one back to new condition.

Have a standard work order made and have a lawyer write  the disclaimer,I never hesitated to scrawl a disclaimer across a work order,or simply refuse to fix something I knew could be unsafe or dangerous.

A lot of their parts are interchangeable,even have same part numbers.