The Myth of the Torque Wrench
Torque wrenches are commonly used for tensioning sawmill blades, but at Woodland Mills, we have learned that the "hand turn" method is far superior to the torque wrench on any models produced from 2020 onward. After extensive testing, we have debunked some common myths about tensioning your blades.
Myth #1: Every Torque Wrench is the Same
There are many different torque wrenches to choose from and they vary in quality and range. We have found that the calibration results differ significantly between them. Something as small as the condition of your grease can impact feedback to the torque wrench making this an unreliable way to tension your blade.
Myth #2: The Blade Will Tension the Same Every Time
We recommend releasing the tension on your blade when it is not in use to protect the rubber belts and keep the mill running smoothly. Over time, the constant application and release of tension cause the threads to polish and the Belleville washers to compress, making it easier to tighten. This can lead to increased tension even while using the same torque specifications.
Myth #3: The Hand-Turn Method is Less Accurate
At Woodland Mills, we proudly introduced the Rapidchange™ Blade Tensioning System in the HM Series of sawmills in 2020. This system allows you to manually tension the blade using the "hand turn" method.
Although tightening the blade by hand may sound less accurate, it self-calibrates for all the factors that may affect torque wrench accuracy including the amount of grease, the height variance in the stack of Belleville washers, and the polished threads. By adopting the "hand turn" method, sawyers can achieve reliable and accurate blade tension every time.
How It Works:
Turn the handle clockwise until "snug". This means that the thrust bearing and the tee handle are just making contact with the Belleville washers, and you start to feel resistance.
Make sure that the blade is no longer drooping between the band wheels.
From the "snug" position, turn the handle clockwise 2.5 to 3 times. This will result in the desired tension every time and require no additional tools.
For more information about blade tensioning refer to the portable sawmill manual found in the black manual tube attached to the product or find it in the "Manuals and Drawings" section of our website.