Section 11: Timing - Checking Loop Lift And Needle Distance - Janome Quilt Maker Pro 18 VERSA Service Manual

11. Timing - Checking Loop Lift and Needle Distance
Figure 11.1
Figure 11.2
Figure 10.4
Loop lift and needle height both set correctly
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Important Note: The timing and needle distance adjustment
must be done with the front machine cover on.
"Loop Lift" is a universal hook and timing term for all lock-
stitch sewing machines. When the needle lifts a specified
distance from the BDC (bottom dead center), the hook point
is set to coincide with the needle as shown in (Figure 11.1)
This is the radial position of the hook called "Loop Lift",
commonly referred to as timing. Another part of timing is the
"Needle Distance" This is the axial distance from the hook
point to the needle. Loop lift is the radial setting of the hook
and needle distance is the axial setting of the hook. Both of
these are set on the hook and fixed with the same set screws.
Since two things are being set at the same time, this can be a
Figure 11.3
4. Place the 2.2 mm feeler gauge between the clamp and the
bottom of the head frame bearing surface (Figure 11.1) .
5. Raise, reset and tighten the clamp, pinching the 2.2 feeler
gauge in between the clamp and projected bearing. This step
may need to be repeated a few times to remove all excess
play between the clamp and gauge.
6. Remove the 2.2 feeler gauge (Figure 11.2)
7. Rotate the handwheel in direction of motion (DOM); is very
important, until the clamp lightly touches the gauging surface.
(Figure 11.3). Important: If the handwheel is turned too hard the
clamp may move, making the check invalid.
8. Check the radial position of the hook point relative to the
needle . (Figure 11.4)
9. Check the axial distance between the needle and the hook
point. The hook point should lightly touch (brush) the needle
inside the scarf. Too much needle distance may cause shredding or
skipped stitches.
little difficult until practiced.
Tools required: Loop lift clamp part #QM40199,
2.2 mm forked feeler gauge part #QM40136, 2
mm ball end L hex tool wrench, 2 mm handle hex
tool and a #3 flat screwdriver.
Check: Observe and do the following before
attempting to make a hook timing adjustment.
1 . Remove the needle plate .
2. Turn the hand wheel until the needle bar is at its
lowest position or BDC (Bottom Dead Center)
3. Place the loop lift clamp (with special protective
compression pad) on the needle bar and set the
thumbscrew lightly.
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