Adjusting The Upper Thread Trimmer Opening Timing - Brother HE-800B Instruction Manual

9. STANDARD ADJUSTMENTS

9-8. Adjusting the upper thread trimmer opening timing

Press the THREAD key to switch to threading mode, and then carry out adjustments.
4104M
Start touching at 1.5 – 2.5 mm
Approx. 0.5 mm
4106M
Gradual opening timing adjustment
1. Loosen the two bolts (3), and then adjust so that the distance (b) between ridge line (B) on the opening cam (1) and the
upper thread trimmer (2) is 0.5 mm, and so that ridge line (B) on the opening cam is parallel to the feed direction.
2. Loosen the two screws (4), and then adjust so that the distance (c) between the rising section (C) of the upper thread
trimmer (2) and the tip of the opening cam (1) is approximately 0.5 mm when the upper thread trimmer (2) is closed.
* If you would like the trimmer to start opening earlier, make the distance smaller. However, if you make the distance
smaller, check that the rising section (C) of the upper thread trimmer (2) does not touch the opening cam (1) and
prevent the upper thread trimmer (2) from opening when the work clamp is lowered.
3. Apply grease to the inclined face (D) of the opening cam (1).
4. Press the THREAD key.
Trimmer fully opening timing adjustment
1. Loosen the two bolts (7), and then adjust the support plate (8) so that the back plate (5) and the cam (6) overlap by
approximately 1.0–1.5 mm.
NOTE: If the amount of overlap is too small, the upper thread trimmer will not open properly and the upper thread
trimmer and the cutter may touch each other.
2. Loosen the two bolts (9), and then adjust the clearance between the bend in the back plate (5) and the cam (6) to
approximately 2 mm.
* If you would like the trimmer to start opening earlier, make this clearance smaller.
3. Check that the upper thread trimmer (2) opens smoothly during feeding.
NOTE: If the upper thread trimmer (2) does not open smoothly, the upper thread trimmer (2) may touch the cutter and
needle breakage may occur.
4. Press the THREAD key.
69
Approx. 0.5 mm
Feed arm
HE-800B
Approx. 2 mm
Approx.
1.0 – 1.5 mm
4105M
3987Q