5.Rotate the speed dial to the desired setting. (The dial can also be rotated while the blade is running.) Refer to the chart in Figure 17 for recommended blade speed and downfeed rate settings.

6.Press the blade run button on the hand grip to start the saw blade.

7.Use the hand grip to slowly bring down the bow until the blade makes light contact with the workpiece. Now begin to apply gradual pressure on the workpiece and complete the cut.

8.Release the blade run button on the hand grip and push the bow back up toward vertical.

9.If finished with the operation, push the STOP button.

Blade Speed and Downfeed Pressure

The Band Saw offers continual variable speed within the specified range; the speed of the blade is set using the speed control dial next to the switch.

A general rule is the harder the material being cut, the slower the blade speed.

Also important is the downfeed pressure, which is the amount of pressure directed by the blade against the workpiece; this is controlled manually by the operator using the grip handle. Downfeed pressure can be deduced by “Recommended Cutting Times” in Figure 17.

Following are general recommendations for speed control dial positions as they relate to the various speeds and applications:

30 m/min. (dial position 1) for stainless steel, alloy steel and bearing bronzes.

45-50 m/min. (dial position 2-3) for mild steel, hard brass or bronze.

60-80 m/min. (dial position 4-6) for soft brass, aluminum or other light materials.

Material chips or shavings are the best indicator of proper blade speed and downfeed pressure. The ideal chip is thin, tightly curled and warm to the touch. Chips that range from golden brown to black indicate excessive force. Blue chips indicate extreme heat from too high a blade speed, which will shorten blade life. Thin or powdered chips indicate insufficient downfeed rate.

Maintenance

Disconnect the band saw’s plug from the power source before doing any maintenance.

Clean the band saw regularly after each day’s work. Clear metal shavings with a suction device or brush, not your hands. Do not use compressed air.

If the power cord is worn, cut, or damaged in any way, have it replaced immediately.

All of the ball bearings are packed with grease at the factory. They require no further lubrication.

Lubricate the vise lead screw with a general- purpose grease.

Inspect the blade blocks (Figure 18). If they are worn, they should be replaced. Remove the blade and replace the blocks.

Figure 18

If the band saw will be unused for a period of time, slacken the blade tension before storage. This will help prolong the life of the blade.

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Jet Tools PB-150, PB-85 operating instructions Maintenance, Blade Speed and Downfeed Pressure