Brother International EF4-B561 Service Manual - Page 22

Procedures Meeting point O 0 0 B A A: Distance between over looper point and needle center when over looper point is at needle plate top. B: Distance between over looper point and needle center when over looper is at left extremity. Single needle (two threads) Over spreader Q for two threads is abail- Meeting point able. Its meeting distance is the same as t that of over looper. Twin needles (mock safety) Replace over looper with mock safety stitch over looper. 7 Remove needle plate. Q'ty of screw 2 8 Make sure that, when over looper 0 meets under looper 0, the point of over looper will pass clear of under 0. Imin looper about 0.1mm below its projected part. 0. I mm Projected part 9 In case of above-mentioned measurement is wrong, direc- 2 tion ® in the figure at right, move over looper back or forth, direction © move over looper driving lever up or down, and fasten them. * If there is a clearance of more than 0.1 mm in direc- tion C), stitches may skip due to the failure of catch- ing loops. Even if there is a clearance of 0.1 to 1 mm in direction C), loops can be picked up, but there is a less clearance between needle and over looper. 10 Install inside cover to flame. 2 j DOUBLE CHAIN STITCH LOOPER MECHANISM Over looper poin Thread - Screw recess - 20 -