Tuesday, June 07, 2016

Brother computerizes Sewing machine – Brother SUPER GALAXIE 3100D - ULT2001N - ULT2001C - M3000N - ULT2003D – Timing belt and motor belt tension adjustments - Presser bar height adjustment – Test mode – Home appliances Repair and service

Category: Home Appliances Repair and Service 

Contents of this article 

  • How to adjust belts tension 
  • How to adjust the needle 
  • How to adjust presser height 

Brother computerizes Sewing machine

TENSION OF MOTOR BELT AND TIMING BELT
STANDARD
There should be a 1.5-3.5 mm slack in the motor belt when the center of the motor belt is pressed with a force of 1N (100g). There should be a 3-4 mm slack in the timing belt when it is pressed with a force of 2N (200g).
ADJUSTMENT
Timing belt
1. Loosen the screw of the belt adjusting pulley.
2. Adjust the position of the belt adjusting pulley.
3. Tighten the screw of the belt adjusting pulley.
Motor belt
1. Loosen the two screws securing the motor holder.
2. Adjust the belt tension by moving the motor holder.
3. Tighten the two screws.
Adjustment Points
1. If the timing belt tension is too loose, the belt may jump while sewing on denim and other thicker fabrics or overlapping fabric, or the feed timing or the closeness of the needle and rotary hook may prevent sewing.
2. If the motor belt tension is too tight, the torque becomes too much, causing the motor to rotate slower and generate an irregular noise.
3. If the motor belt tension is too loose, the belt may jump and the upper shaft may not rotate smoothly while sewing on denim and other thicker fabrics or overlapping fabrics, the motor may not rotate smoothly, or the upper shaft may not rotate.
NEEDLE DOWN POSITION ADJUSTMENT
STANDARD
When test mode "4" is selected, the needle should be exactly at the middle of the needle plate hole in the needle down position.
ADJUSTMENT
1. Select test mode "4".
2. Turn the balance wheel to move the needle to the needle down position.
3. Loosen the screw securing the zigzag connecting rod assembly.
4. Press the keys on the display to move the needle to the left and right, and then turn the zigzag adjusting nut by using the box wrench to set the needle in the center of the needle hole.
5. Tighten the screw securing the zigzag connecting rod assembly.
6. Press the keys on the display to move the needle to the left and right and check the needle down position.
Test mode for main PC board only
(3-point needle drop, alarm check)
1. Turn on the power with the front cover removed.
2. Press the SW5 switch.
The main seam position will change each time it is pressed: left seam position  middle seam position  right seam position.
3.
# Press the SW1 switch, make the feed 0, and operate at the lowest speed.
# By pressing the SW3 switch, the conditions will change as follows:
Low speed (70 RPM) Feed = 0 (Original condition)
In the conditions described above, press SW5 to change the seam position without regard to the needle position:
left seam position > right seam position  left seam position …
Medium speed (410 RPM) Feed = 0
In the conditions described above, press SW5 to change the seam position without regard to the needle position:
left seam position > right seam position  left seam position …
High speed (850 RPM) Feed = 0
In the conditions described above, press SW5 to change the seam position without regard to the needle position:
left seam position  right seam position >  left seam position …
High speed (710 RPM) triple zigzag Feed = Maximum (4mm), Z = Maximum (7mm)
Low speed (70 RPM) Feed = 0
NEEDLE BAR HEIGHT
STANDARD
When test mode "5" is selected, turn the balance wheel so that the needle meets the rotary hook point. At this time, the clearance between the upper end of the needle eye and the bottom of the rotary hook point should be 1.0-1.4 mm.
ADJUSTMENT
1. Select test mode "5".
2. Turn the balance wheel so that the needle meets the rotary hook point.
3. Loosen the screw of the needle bar block assembly.
4. Move the needle bar vertically to adjust the clearance to between 1.0-1.4 mm.
5. Tighten the screw of the needle bar block assembly.
NOTE :The needle bar clamp should be parallel to the side of the needle plate. If the needle bar is loose when you adjust the needle bar height, it may result in sewing troubles.
Adjustment Points
1. If the needle bar height is too low or too high, skipped stitches, split thread or cut thread may occur.
2. While adjusting the needle bar height, check the needle threading hook.
PRESSER BAR HEIGHT
STANDARD
The clearance from the needle plate top to the bottom of the presser bar should be 7.0-7.5 mm.
ADJUSTMENT
1. Raise the presser foot lifter.
2. Loosen the screw of the presser bar guide bracket.
3. Adjust the height of the presser bar by moving it vertically.
4. Tighten the screw of the presser bar guide bracket.
NOTE :The presser foot should be positioned in the center of the needle hole of the needle plate.
Adjustment Points
1. Install presser foot J.
2. When adjusting the presser bar height, the presser foot should be parallel with the feed dog hole in the needle plate.
# A hexagonal pencil can be used to check the height.
3. If the presser foot is not parallel with the feed dog hole, the needle may contact the presser foot or the fabric may not feed straight while overcasting.
# After the presser bar height is adjusted, be sure to adjust the fabric thickness detector using test mode "2".
TIMING BELT TENSION FOR THE X DIRECTION
STANDARD
There should be 4 mm slack in the timing belt looped around the X driving shaft and the X tension pulley shaft, when the center of the belt is pressed by a force of 1.2 ± 0.12N (120 ± 10g) after the X carriage unit is moved all the way to the right.
ADJUSTMENT
1. Move the X carriage unit all the way to the right.
2. Loosen the screw of the X tension pulley.(screws (A) and (B))
3. Adjust the position of the X tension pulley.
4. Tighten the screw of the X tension pulley.(screws (A) and (B))
Adjustment Point
If the tension in the belt is too weak or too tight, the embroidery may not be aligned correctly (the inside of the pattern may not align with the outline).