Adjusting The Lower Thread Clamp Timing; Adjusting The Bobbin Presser; Adjusting The Needle Up Stop Position - Brother HE-800A User Manual

10. STANDARD ADJUSTMENTS

- . Adjusting the lower thread clamp timing

Becomes
faster

- . Adjusting the bobbin presser

-

. Adjusting the needle up stop position

77
Becomes
slower
3988Q
3989Q
3990Q
HE-800A
When reference line A on feed guide shaft B (1) is
aligned with the edge of the feed arm support (2), the
opening plate (3) will start moving when the feed
mechanism moves 6 - 7 mm from the home position,
and the lower thread retainer (4) will open.
To change the opening timing, loosen the screw (5) of
the feed arm support (2) and move feed guide shaft B
(1) to the left or right.
1. Set the sewing machine to the home position and
then press the RESET key.
2. Loosen the set screw (1), and then adjust so that
the bobbin presser (2) goes into the hole in the
bobbin case (3).
3. Check that the work clamp is at the home position,
and then loosen the nut (4) and turn the screw (5) to
adjust the clearance A between the bobbin presser
(2) and the edge of the bed to approximately 12.5
mm.
The needle up stop position is adjusted so that the
index mark (2) on the machine pulley (1) is inside the
mark (4) on the belt cover (3).
If adjustment is necessary, loosen the screw (5) of the
machine pulley (1). The machine pulley (1) will stop
more slowly if the screw (5) is moved counter to the
normal direction of rotation, and will stop more quickly
if the screw (5) is moved in the normal direction of
rotation.
Note:
The screw (6) at the "D" mark is an adjusting screw
for the needle down detection function and is
adjusted to match the feed timing, so it should not
be loosened.
* If the index mark (2) is not inside the mark (4) when
the sewing machine is started, and error code "E-02"
will be displayed. Turn the machine pulley to move
the index mark (2) to the correct position and then
start the sewing machine.