Make accurate adjustments with a dial indicator. See Figure 23-64. Without the indicator, make the same comparisons with a wood block. However, this method is less accurate. At times, handwheels become hard to turn. First, check to see that the lock knobs are loose. If they are, lubricate screw threads with silicone spray or pow- dered graphite. Sawdust will stick to oil and may create a condition worse than before. There may be times when you may smell rubber or varnish around a table saw. A rubber scent can occur when the belt is not tracking properly. The belt overheats and may harden. Then it can crack and possibly break. An overheated motor has a definite varnish-like smell. Motors have a built-in fan to keep them cool. It can attract sawdust. Sawdust accumula- tion can obstruct the airflow and cause the motor to overheat and possibly burn out. Rust occurs on unpainted steel parts. Remove the rust with oil and steel wool or fine emery cloth. Wipe the oil away because it will stain your wood. Then coat the table and other parts with paste wax. Wax is less likely to be absorbed into the wood. 23.12.2 Radial Arm Saw A radial arm saw has many movable parts. Rust, lack of lubrication, and excessive torque on levers are sources of maintenance problems. Check table and fence alignments before making cuts. Do so with a square, protractor, T-bevel, or other device. Machine scales may not be accurate. The table may have to be leveled so the blade will be square. Do so by removing the table protector and wood top. Adjust the leveling bolts as necessary and reset the locknuts. See Figure 23-65. Sometimes the saw kerf is not straight. The saw assembly movement bearings inside the overarm could be out of adjustment and allowing side play. Patrick A. Molzahn Goodheart-Willcox Publisher Figure 23-64. With the fence clamped, check the distance from the fence to a table slot at both the front and back. Lock knob T-slot Table Fence Compare Readings at Both Ends Dial indicator Patrick A. Molzahn Goodheart-Willcox Publisher Figure 23-63. Check distance readings from the blade to the table to determine whether the arbor and table are aligned. Blade or metal plate Table insert opening Dial indicator T-slot Compare readings 404 Section 4 Machining Processes Copyright Goodheart-Willcox Co., Inc.