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A>B Good FIG 1 b. Eyebolts must be threaded all the way in and tightened. c. Two eyebolts are safer than one and can help prevent the mold from tilting . d. Ideally, the location of the eyebolt is at the mold's center of gravity, so it does not tilt. 4. Check the size and condition of the nozzle se at. It will be dif- ficult to check after the mold is installed. a. Write down or find an appropriate nozzle tip type and size before you forget. 5. Ensure the carriage is back and/or the screw is forward. a. Be alert for resin drool or spitting. b. The barrel heats may be on or off, depending on the situation. 6. Check that the resin is not degrading in the barrel from sitting there too long. a. Many materials, such as PVC or POM (acetal), produce gases that can develop high pressures within the barrel. 7. Clean the machine platens and the mold's clamp-plate faces. a. Check for "dings" or raised areas on the mold and platen—espe- cially the locating-ring alignment hole. Stone flush if necessary. 8. Check for damage to the clamp bolt thre ads in the platens. 9. Spray a light mist of "overnight" preservative or WD-40 on the platens and the clamp-plate faces of the mold. 10. Check that the clamp bolts ha ve the correct thread type: English (SAE) versus Metric. 11. Check that the clamp bolts are the correct length. a. If the bolts are too short, with insufficient engagement, or too long and "bottom out," you can strip the threads in the platen. 12. Lubricate the clamp bolts. a. If the bolts are not lubricated, 85% of the torque is used to overcome friction and only 15% is available to produce bolt load. If the bolts are lubricated (with cadmium plate, molybdenum disulfide, anti-seize compounds, etc.), the friction is reduced and greater preload is produced with the same torque. 13. Check that the crane can adequately lift the mold over the machine's tiebars. a. Check for obstructions above the machine, such as sprin- kler heads, ceiling fans, etc. b. Check that the robot, picker, or other automation is safely out of the way. 14. Lift the mold up over the tiebars and lower it into the molding area. a. Keep your fingers away from the chain links. b. Make sure no one is in the immediate area during this process. Use safety cones, barrier tape, or other preven- tive measures. 15. With your hand on the side or top edge of the mold, guide it into the machine and engage the locating ring into the align- ment hole in the fixed platen. a. Do not let the edges or corners of the mold hit the platens or tiebars. IN SETUP MODE: 16. This is a good time to check the machine's safety switches. 17. Advance the moving platen until it just touches the back of the mold. a. You can make sure the locating ring remains engaged in the platen alignment hole by occasionally looking at it from the barrel side. WITH THE PUMP MOTOR OFF: 18. Open the gate and level the mold. TABLE 1 Fastening the Mold to the Platen: Minimum Depth in Cast Iron The clamp bolt should always be closer to the toe than the heel. Bolt Size & Pitch, in. Depth, in. Full Turns ½ -13 1 13 5/8 - 11 1.25 14 ¾ - 10 1.5 15 1 – 8 2 16 No single procedure is correct for all applications. A=B OK AB Good B B B A A A FIG 1 @plastechmag 53 Plastics Technology M O L D M O U N T I N G