For over 30 years of cutting at least five cords of firewood every Winter, I always used to hand file my saw chain in the field, but as the chain wore, got dinged and the file wore, the minor inconsistencies stacked up to degrade the quality and longevity of the cut. Swapping a sharp chain for dull one in the field is more efficient, as is setting up my new Oregon 410-120 chainsaw chain grinder to sharpen four to six dull chains in turn at one sitting, like an assembly line. I purchased a separate CBN(Carbon Boron Nitride) super abrasive wheel, over the stock pink Aluminum Oxide grinding wheel for a smoother grind finish and longevity with the frictional heat being absorbed by the aluminum wheel body, to prevent overheating each chain cutter tooth, which may explain the fan-cooled motor housing getting hot to the touch. I built a simple plywood “bookend” portable mount so I could just “C”-clamp the grinder to my folding sawhorse, then easily store it when not in use The grinder set-up and operation are pretty straight forward, but the cutter tooth backstop and grind depth indices need to be adjusted when switching to grind opposite side cutters. Since the motor only rotates in one direction, the wheel leaves a burr exiting the left-hand cutter teeth. When grinding down the depth stops with the 1/4” thick pink Aluminum Oxide grinding wheel provided, the right-hand depth stops tend to catch abruptly and are pulled in under the wheel, as they lean out away from the wheel, toward the operator, and the chain is not centered under wheel’s lowest tangent point, so they catch and try to stand up vertically into the wheel. The Left-hand depth gauges lean the opposite way, so as not to catch in this manner. Safety glasses are a must, but the grinder is fairly quiet, so no hearing protection required. In the open shade of my carport, the LED light didn’t add much, but probably would in a dimly lit garage or shop. For weeks I’ve been battling a two-foot diameter Japanese Maple stump. It is so hard and gnarled, that it just bogged my faithful Stihl 028 saw and quickly dulled and cooked a brand new Stihl 33RSF72 Full-Chisel skip tooth chain. Several hand-file resharpenings made no difference, but after sharpening it on my new grinder, with stock 30*-60*-10* angle settings, I finally managed to chew my way through the stump before it dulled! Another sharpening and one final slice should get it below grade for permanent burial and end my long nightmare -Yah!????????????????
