Yeah the timing is off

A quick (rough) check of the "timing" is possible while the shuttle is out. The needle should be at its lowest position when the point marked with a green dot above is directly below the right side of the feeddog. The timing can drift for various reasons - sewing heavy material or very thick designs, for example - where the symptoms can include nesting and other stitching problems. The drift is usually due to parts on internal shafts rotating slightly from their desired position;correction requires loosening the set (grub) screws, aligning timing marks, and retightening the set screws - not easily done by most owners.

Step by Step photos:
http://www.annsultfixit.com/UltFixit.html#Timing

When and how should I time the machine?

The good news is that APQS machines are carefully set at the factory byskilled technicians; therefore, the timing rarely needs adjustment.

When it does, it’s typically the result of something unusual happening,such as a cleaning rag getting swept into the hook assembly (hint: keepyours well away from the hook area when oiling it) or a severe needlejam. If neither of these disasters has happened to you and you stillare wondering if the timing needs adjustment, here’s what to look for:

Skipped stitches: On stitch-regulated machines, does it happen institch-regulated mode but not in manual mode? Check to see if there isa needle hole in the fabric where the skipped stitch occurred (bymoving thread out of the way). If there is no needle hole in the fabric(it looks like a long stitch), your stitch regulator probably justneeds adjustment. However, if it happens in both stitch regulated andmanual mode, then the timing might need adjustment.

The needle hits the bobbin: First make sure you have correctly insertedthe needle with the scarf to the back of the machine and that theneedle is inserted all the way into the needle bar shaft. Make sure theneedle is not bent—try a new needle. Listen for clicking noises andcheck the bobbin edges for wear or burrs.

Frequent needle breakages: If you are sure the needle is insertedcorrectly, and that other factors such as bulky seams or impropermachine movement are not causing the breaks, and then re-timing may benecessary.

Re-timing your machine:

Step 1: Set the needle depth.
This first step is critical to successfully setting the machine’stiming. The needle must not be too high or too low. Remove the bobbincase. Put a new needle into the needle bar, and then lower the needleto its lowest position, using the hand wheel. Look from the front ofthe machine into the hook assembly. You should be able to see theentire needle eye. If you can, then move on to Step 2.

If you must adjust the needle bar, then use a long, straight tipscrewdriver to loosen the needle bar clamping screw. The access holefor this is located directly above the fluorescent light on the frontof the machine. (If you have a Millennium or Liberty, the front coverwith the speed/stitch length gauge will have to be removed first togive you access to the hole.) Adjust the needle bar so that you can seethe entire needle eye in the hook assembly, then re-tighten the screw(and replace the cover if needed.)

Step 2: Check for proper hook rotation.
With the needle bar in its lowest position, rotate the front hand wheelslowly in a clockwise direction (up on the left side, down on theright) while observing the scarf (that’s the notch in the back of theneedle) and the point of the rotating hook assembly. As the needlebegins its upstroke, the point of the hook should pass the needleslightly below the midpoint of the scarf. (Check your manual for adiagram of the scarf position.)

To adjust the rotation, you may advance or retreat the hook (rotate itleft and right on the shaft) by loosening the three large set screws onthe backside of the hook that secure it to the rotating shaft.Reposition the hook by twisting it on the shaft while holding the handwheel (and thus the needle) stationary. Once the proper rotation isachieved, slightly tighten one of the set screws on the back of thehook. Wait to retighten all of the screws until after you’ve completedStep 3.

Step 3: Check for needle/hook clearance.
To assist you with this step, you should have a magnifying glass (wefound a terrific 2 in. x 2 in. magnifier at Ace Hardware for around$7). Without a magnifying glass, you may think that your hook point istouching the needle when actually there is still space or “daylight”between them. If you can get a piece of paper between the point of thehook and the needle without force or flexing of the needle, you willstill get skipped stitches. When the timing is properly set, you willsee NO daylight when using the magnifying glass. In fact, the point ofthe hook has to just slightly move the needle and cross the needle justbelow half way on the scarf, as in Step 2.

To close the spacing between the hook and the needle, use a flat bladescrewdriver to gently pry the hook forward (bringing it closer to theneedle) WITHOUT changing the proper rotation you set in Step 2. If,however, the hook point is hitting the needle too hard (bending theneedle), the hook needs to be slid backward (away from the needle) tothe point where it just slightly deflects it.

Once this position is set (double check with your magnifying glass) andyou’re sure the rotation has not changed from Step 2, and thenre-tighten the hook set screws. Turn each screw in a small bit at atime, so that each one is tightening its grip on the shaft equally. Ifyou tighten one screw completely before moving on to the next, you riskthrowing off all the work you’ve done by causing the hook to slide onthe shaft.

Step 4: Adjust the hook retaining finger.
The hook retaining finger keeps the bobbin basket from rotating insidethe hook. You can see it by looking down into the hook area from thetop of the machine. It extends from the front of the machine toward thehook assembly. You’ll notice a notched area on the bobbin basket (thepart of the hook where the bobbin case rests).

The retaining finger must protrude into the notched area only farenough to keep the bobbin basket from spinning (about 1/3 of the wayin). The thread passes between the finger and the bobbin basket—if itis in too far, the thread will get hung up and break. If adjustment isneeded, loosen the single Phillips head screw holding the finger inplace (under the throat plate area near the front of the machine) andslide the hook retaining finger to the proper position. Retighten thescrew. Finally, make sure there are no burrs on the finger that may cutthe thread!

Step 5: Perform a “dry run.”
After you’ve completed all the adjustments, take the time to turn thefly wheel by hand to check your work. Make sure the needle doesn’t hitthe hook, that the clearance is correct, and that the retaining fingeris correctly positioned. It’s much wiser to find any misalignments nowthan to turn on the machine let it find the misalignments for you!

Timing can be intimidating at first...but we can walk you through it and you will be so glad you learned how to do it!

Benjamin

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