6
SYNCHRONIZING LOOPER AND NEEDLE MOTIONS
Synchronization is the most important adjustment
involving the needle and looper motion relation,
because it maintains the needle-looper relation at
both the needle loop taking time, as well as when
the needle enters the looper triangle. This adjustment
is best made using synchronization gauge set TT34.
Remove the throat plate, feed dog, looper and
needle thread take-up wire, (also called strike-off
wire). Fig 3 Using gauge set TT34, attach the synchro-
nizing plate (A) to the throat plate support with the
throat plate screws. Insert the pin (B) into the hole
for the looper and tighten with its screw. Turn the
handwheel in operating direction, (towards the
operator), until the pin lightly touches the right edge
of the synchronizing plate. Insert the indicator (C)
into the hole for the needle thread take-up wire, and
move it up or down until the pointer (D) on the
indicator reads at "0", and then tighten the screw.
Now turn the handwheel in opposite of operating
direction (away from the operator), until the pin
again lightly touches the right edge of the plate. If
the machine is synchronized the pointer on the
indicator should again read "0". If the pointer is
above or below the "0", the machine is out of syn-
chronization. A variation of one line is allowable.
To synchronize the machine the following procedure
should be followed. Thread screw (F) (99271), from
gauge kit TT34, into the looper drive lever rocker shaft
through the center of the thrust adjusting screw.
If the pointer (D) on the indicator reads above the "0" (Fig. 3A). Loosen screw (E) in the looper drive
lever and pull screw (F), (99271), slightly toward the operator. Retighten screw (E) in the looper drive lever
and recheck the synchronization as outlined above. Repeat as necessary to obtain proper synchroniza-
tion.
If pointer on the indicator reads below the "0", (Fig. 3B). Loosen screw (E) in the looper drive lever and
tap screw (F), (99271), slightly away from the operator. Retighten screw (E) in the looper drive lever and
recheck the synchronization as outlined above. Repeat as necessary to obtain proper synchronization.
If synchronization gauge set TT34 is not available, the following procedure can be used.
Fig 3
Fig 3A