Brother International T-8422C Instruction Manual - English - Page 78

13. STANDARD ADJUSTMENT 13-7. Needle and rotary hook timing 1. Set the stitch length dial to the actual length of the stitches to be sewn. Standard stitch length Specifications -T[]F -[][]3 -405, -407 Stitch length dial 2 2 3 2. Remove the rubber cap (1). 3. Loosen the screw (5) and move the needle bar (2) up or down to adjust so that the top reference line (3) on the needle bar (2) is aligned with the bottom edge of the needle bar bracket (4) when the needle bar (2) is at its lowest position. (Be careful not to turn the needle bar (2) at this time.) 4. Securely tighten the screw (5). 5. At this time, the gaps (A) and (B) between the needle (6) and the front of the feed dog (7) should be about the same as each other. Needle bar lowest position Lower feed 2203B 6. Turn the machine pulley forward to raise the needle bar (2) until the reference line ((8) or (9), depending on the feed condition) on the needle bar (2) is aligned with the bottom edge of the needle bar base (4). 7. In this condition, secure the machine pulley with tape or similar, so that the needle bar (2) will not move. The procedure up to this point determines the needle bar lift amount. Needle feed NOTE: If the needle bar lift amount is too large • It will cause poor tightening in the right thread. • Both the left and right seams will become uneven, and skipped stitches or thread breakages will occur. • Upper thread trimming errors may occur, or the upper thread may be cut too short (models with thread trimmer). • The upper thread trailing length will be too long (models with thread trimmer). 3040M If the needle bar lift amount is too small • Skipped stitches and thread breakages will occur. • The upper thread trailing length will be too short (models with thread trimmer). 69 T-8421C, 8422C, 8452C, 8722C, 8752C