Document XOgdDvvD6OJvzwDy7B5XKJdkR

MACHINE TOOLS a spring release to return the guard to a position clearing the work. Each guard should have an automatic interlock so that the machine will not operate except when the guard is m place. On some makes of machines still in use, the lever which controls the direction of operation of the spindle is located so that the operator's hand may be caught on the back gears driving the spindle. An auxilia ry lever should be installed which can be operated at a point outside the danger zone created by these gears. On large machines where the operator may not be dose to the regular control switch, a pendant switch mounted on an arm or sweep should be installed to operate a magnetic brake so that the machine can be stopped instantly When the operator inserts an arbor into the spindle, he should be sure that both ar bor and spindle holes are dean and free from mdcs He should draw the arbor firm ly into place by a sleeve nut, and securely tighten the nut Before he removes the ar bor from the spindle, he should make cer tain that the machine is at a standstill. Planing Machines Similar to a carpenter's hand plane, a planer machines a metal surface with the cutting tool held stationary while the work is moved bade and forth underneath it Shapers are generally classified as planing machines, but the process is reversed--the work is hdd stationary while the cutting tool is moved back and forth. Other ma chine tools coming within this classification are slotters, broaches, and keysealers Planers and shapers Planer accidents result frequently from unsafe practices which are basically prob lems of training and supervision 1 Placing the hand or fingers between the tool and the work 2 Running the bare hand over sharp metal edges 3 Measuring the job while the machine is running 4 Failing to damp the work or tool secure ly before starting die cut. 5. Riding the Job. 6. Having insufficient clearance for work. Fig. 24-9o. A guardrail or similar barrier should close off any space 18 in or less between a fixed object and parts of a fully extended ploner or its stock. Openings In the bed of the planer should be filled to eliminate shear hazards. 7 Coming in contact with reversing dogs 8 Failing, when magnetic chucks are used, to moke certain die current is turned on before starting the machine The reversing dogs on planers and shap ers should be covered If the planer bed, when fully extended, or any stock on the bed being processed, travels within 18 in of a wall or fixed objects, the space between the end of the travel and the obstruction should be closed by a bamer on either side of the planer (Fig 24-B) Shaper accidents have essentially the same causes as planer accidents In addi tion, injuries frequently result from contact with projections on the work or with pro jecting bolts or brackets, especially when the table is being adjusted vertically. The ram of the shaper should be left projecting over the table so that the operator will know when the table is high enough Failure to locate the stops or dogs prop erly may cause injury to shaper operators The stops should be ngidly bolted to the table, especially on heavy jobs The shaper operator should make sure that die tool is set so that if it shifts away from the cut it will rise away from the cut and not dig into the work. The handle of 24-10