How to Set Rotary Hook Timing on an Embroidery Machine

In this video, we set the hook timing with the rotary hook support already in place. We explain that hook timing is the relationship between the point of the rotary hook and the needle. The hook point should pass through the needle scarf, or cutout section, approximately in the middle. We check two relationships: left to right, where the hook point must sit directly behind the needle, and front to back, where it should be between one-tenth and three-tenths of a millimeter behind the needle.

To check the left-to-right position, we stand directly in front of the needle and look straight toward the back of the machine. The tip of the rotary hook should disappear behind the needle, not show before it or slightly after it. For the front-to-back setting, we use one of two methods. If we are experienced, we can gently push the needle back with a screwdriver resting on the rotary hook support and look for only the slightest needle deflection. If the needle does not move at all, the hook is too tight against it. Another method is to remove the needle, turn it so the scarf faces the front of the machine, bring the rotary hook forward until it touches the needle, and then reinstall the needle correctly with the scarf facing the back.

We then fine-tune the hook position, rechecking both directions after each adjustment. Once the hook point is directly behind the needle and there is only a slight amount of deflection front to back, we verify that the indication dial is still at 200 degrees. After confirming the hook is passing through the scarf at the correct point, we seat the set screw carefully so the hook does not shift, rotate the indicator wheel to 160 degrees and tighten that screw, then return to the set screw. Finally, we go back to 200 degrees and confirm the hook timing still looks correct. With the hook directly behind the needle and the proper front-to-back clearance, the rotary hook timing is complete.