1. Mismatched thread pitch between locknut and spindle threads.

Examine thread pitch of both locknut and spindle, making sure they match.

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2. Warpage at threaded area of spindle.

Measure three equidistant points on the spindle thread diameter with needle gauge to determine any discrepancy.

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3. Superficial damage to thread ridges, or fragments thereof.

If threads are damaged or any fragments thereof can be found, smooth out with a fine triangle file, clean, lubricate, and reassemble.

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4. Possible reverse threading of either spindle or locknut.

Examine to determine if thread directions conflict. If they do, you are using the wrong locknut.

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5. Mismatched thread diameters.

Measure both thread diameters with calipers to be sure the sizes match.

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6. External spindle thread diameter too large.

Use feeler gauges to determine thread sizes match.

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7. Non-standard spindle thread specifications.

Use a profile projector to be sure spindle threads are at 60 degrees.

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1. Slackened off lock screws.

If the lock screws are loosened off and the lock nut still won't come free, it could mean the copper thread locks which the lock screws tighten against are jammed against the spindle threads. Lightly tap at the locking screw locations to jar them free. Snug up each lock screw and loosen off once again to free the locknut.

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2. Dirty threads.

Clean all threads and surfaces with an appropriate industrial cleaner and lubricate properly

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3. Damaged threads.

If threads are damaged or any fragments thereof can be found,smooth out with a fine triangle file, clean, lubricate, and reassemble.

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1. Threads that match, but have too much slack between them.

Check to see if external threads are too small.

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2. Wrong choice in model of locknut.

According to the type of machine, the correct model of locknut must be chosen. Consult an Yinsh agent for proper selection.

 

 

 

3. Improperly tightened locknuts.

Be sure that locknut is tightened with a torque wrench and that lock screws are evenly tightened.

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1. Lack of parallelism between spindle center and its outer threads.

Have the spindle threads professionally re-turned or re-ground.

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2. Unequal tightening of lock screws.

Back off all lock screws and finger tighten evenly. Then tighten incrementally with even pressure.

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3. Use of wrong tool in tightening lock screws.

Do not tap to adjust. Must employ use of proper torque wrench.

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4. Dirty threads.

Clean all threads and surfaces with an appropriate industrial cleaner and lubricate properly

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