Brother International EF4-B561 Service Manual - Page 23

Procedures Q'ty of scr ew 1 Temporarily fasten double chain stitch looper holder 0 on longitudinal feed shaft 2 Install double chain stitch looper 0 by inserting it all 1 the way into double chain stitch looper holder 0. The inclination of the looper depends on the screw recess. 3 Install double chain stitch needle into needle clamp. The below items of 0 and 0 should be taken simultaneously. 4 In case of standard specifications, make an adjustment so that the distance between the looper point and the center of needle is 1.5mm when double chain stitch looper comes to the leftmost position. In case of highlift specifications, that distance is 1.3mm. (Sidewise potioning) 5 Position the looper so that, when the looper point is in line with the needle center on the needle's upward travel, the looper point will be at about 0 to 0.05mm from needle, and then fasten double chain stitch looper holder. (Longitudinal positioning) * When stitch-skips occur, adjust it that the looper point will hit needle about 0.05 to 0.1mm deep. 6 Install double chain stitch needle guard (F) 0 to that 1 of (B) 0 in order to make clearance about 0.3 to 0.5 mm. 7 Temporarily fasten double chain stitch needle guard (B) to needle plate support bracket. 0 .3-0 .5mm---iAix Standard specifications 1.5 mm High-lift specification 1.2 mm 0 -0 05mm CD C) 8 Match the looper point with the needle center on the needle's upward travel, hold double chain stitch needle guard (B) in contact with the needle, adjust the clearance between the looper point and the needle to 0 to 0.05 mm, and fasten double chain stitch needle guard (B) securely. 0 -0.05mm [1] KNIVES MECHANISM 4)- (7) L® 3 - 21 -