A sewing machine's timing is critical to proper stitching.
The timing of a sewing machine describes the relationship between the sewing machine needle and the hook. When the timing of these two elements is off, it leads to problems with the sewing stitch such as producing no stitch or intermittent stitching. The bevel gears which drive the hook assembly need to be adjusted to correct this problem. This requires tipping the sewing machine upward and adjusting set screws in the bevel gearing.
Instructions
1. Set the stitch length for your Singer machine beyond 32 or until there is no forward motion of the needle. Other machine types may be different and you should consult your manual for instructions. The needle bar should go straight up and down and the fabric will not move forward. Remove the needle plate which is under the pressure foot. Before removing the bobbin casings note how the tab slides into the underside of the needle plate. When putting the machine back together, the tab must slide back into the slot.
2. Remove the bobbin casing from contact with the needle plate by sliding the bobbin casing tab out of the slot. Do this for all bobbins. Examine your needles to make sure they are perfectly straight. If you think they may be bent, replace them with new needles. Find the marks on your needle bars by rotating the needles into the lowest position, there should be a horizontal mark 1/4-inch below where the needle bar enters the frame.
3. Turn the balance wheel until each needle bottoms out and starts back up. Stop when the marks on the needle bars just enter the frame. Locate the hooks. When the needle bar has just entered the frame, the hook for that needle bar should be crossing the center of the needle about 1/16-inch above the eye of the needle. If the hook and needle and needle bars do not match this description, then the sewing machine's timing needs to be adjusted.
4. Release the latches that hold your sewing machine in its case. Tilt the sewing machine to view the bevel gears that drive the hook assemblies. These gears rotate around the vertical axis. Unscrew the screws that attach the bevel gear to the hook assembly. Be careful not to strip the screws. If necessary, file the screw tips to fit the heads tight.
5. Loosen the assembly. Adjust the timing so that the hook is passing across the center of the needle 1/16-inch above the screw eye when the needle bar has just entered the frame. When you see this alignment, tighten your set screws. Test for stitching. Set the needle plate back in position and slide the tabs on the bobbin casings back into the slots on the underside of the needle plate.
6. Test the timing by sewing a few stitches. Make further adjustments until the timing is right. You may need to fiddle with your hooks if they have play. Play is a term used to describe looseness from wear. Try rotating them counter clockwise against the play before you tighten the screws.
Tags: sewing machine, needle plate, needle bars, 16-inch above, back into, bevel gears, bobbin casing
