Adjustment may or may not be possible. If not, the bearings will need to be replaced. 23.12.3 Band Saw With band saws, you must be able to apply the proper blade tension and adjust the tilt on the upper wheel for tracking. See Figure 23-66. You must also be able to align the upper and lower blade guides and set the rear blade guide for different blade widths. Blade Tension Blade tension is controlled by a tension control knob, Figure 23-67. It moves the upper wheel toward Patrick A. Molzahn Figure 23-65. A radial arm saw table should be flat and level. Remove the table and adjust the bolts under the platform. Patrick A. Molzahn Figure 23-67. The tension control has a scale to indi- cate proper tension for various width blades. Goodheart-Willcox Publisher Figure 23-66. The upper wheel on a band saw blade raises and lowers for tension adjustment and tilts for tracking adjustment. Tension knob Tracking knob Tension scale Tension Tilt Blade Rubber tired wheels or away from the lower wheel. Most machines have a scale and marker to note proper tension for a given blade width. Depending on the age and quality of the tensioning spring, the scale may or may not be accurate. The best way to tension a band saw is to use a tension gauge. If a gauge is not available, try pushing on the side of the blade. It should deflect no more than 1/8″–1/4″ (3 mm–6 mm) under moderate pressure. Blade Tracking The tracking adjustment moves the upper wheel toward or away from the operator. The adjusting mechanism is typically located on the back of the upper wheel housing. See Figure 23-68. When a blade is installed with the proper tension, turn the upper wheel slowly. Make sure the blade remains centered on the tire. Turn the wheel at least three or four revolutions. Adjust the tracking knob or screw as necessary. When you are confident that the blade Chapter 23 Sawing with Stationary Power Machines 405 Copyright Goodheart-Willcox Co., Inc.