The adjustment of JK373 Button attaching machine: When the machine is braking, the presser foot is completely up to the highest point, standard distance between wire cutter plate (front) and the needle plate is 13mm.

Standard spacing adjustment; remove the head base baffle plate, and then loosen the two nuts, screws for connecting mobile before and after, use the model to adjust the spacing to 13mm, then tighten the two nuts. When tightening the nut, wire cutter webs should be in a horizontal position.

Acting trimming knife hook height adjustment:
Stripping hook height standard: the distance between a hook and line should be maintained at 0.5 ~ 0.7mm. If not, you can bend wire hook a little.

Lifting lever and the adjustable screw adjustment
The distance between the top of the lifting lever and adjustable screw ought to be 0.5mm. Loosen the lock nut, turn the screw up and down, transferred after a gap of 0.5mm, and tighten the lock nut.

Common fault causes and treatment methods
Do not cut the line
Wire hook could not reliably poke a side of fabric. So adjust the position of the thread cutting knife; sewing machine needles do not fall into the center of the eye button, rolling head holder to adjust; in the final stitch point, adjust the needle and looper (relative position); if the height of cutting knife is inappropriate, adjust it.

Needle thread and thread on the back of the fabric are cut
if the position of acting trimming knife does not fit, adjust the position of knife when machine finishes braking.
After the thread is cut, the thread on the back of the fabric is exposed too long.
Maybe the timing of thread cut knife is inappropriate, adjust the position of it. If the reason is the uplift amount button presser device is too large, ries the button clamp jaw to 9mm.