Janome 1200D Manual page 30

CHAIN LOOPER : ANGULAR POSITION - CLEARANCE - ORBITAL
TIMING - CLEARANCE OF CHAIN NEEDLES GUARD
1. Remove: Mains lead - Sewing foot - Machine base - Needle plate.
2. Make sure that there is no axial play on chain looper shaft "a". If necessa ry, adjust
with stop collar inside shaf t "g" in Fig.6 in page 11c .
3. Angular position of chain looper: Insert a new needle (No 90) in "L2". Chec k height
and orie nt atio n of needl e bar in pag e 5. Brin g chai n loope r t o it s far rig ht swin g
position . Check distance from point of chain looper to chain needle wit h thic kness of
gauge. If necessary, loosen screw "c" just enoug h to adjust th e chain loope r arm "d"
angularly to obtain a clearance of 1.5 to 1.8mm . Then tighten scr ew "c".(Fig.1)
Note: At this step, an easy check of the chain looper timing can be done as f ollows:
Chai n looper motio n right to left and the needle bar stroke should start at the same
tim e. Turn the handwheel towards you, bring the chain looper eye from right to left
motion behind the cover hem needle eye "L0". Chec k if eye of chain looper matches
wit h eye of needle (eye to eye).(Fig.2) If not, recheck all the above adjustments and
adjus t timin g st rok e wit h eccent ric "5" . See pag e 3a & 3b for th e positio n of
eccentric. The eccentric "5" is used for bot h chain and lower loope r timin g. When
adjusting thi s timin g, make sure that you also check the adjustment of lower looper
stroke.
( See page 6 and 8 )
4. Clearance of chain looper : Bring poi nt of loope r - from rig ht to left - behind th e
cover hem needl e "L2", and check if clearance is less tha n 0.05mm. Then bring ti p of
loope r behind the cover hem needl e "L0", and check if clearance is less tha n 0.05m.
(Fig.3)
5. Clearance of chain needle(s) guard: Turn handwheel towards you unti l coverhem
needle(s ) app roache s t o chai n needl e guard as close as possible . At this time , the
clearance between coverhem needle(s) and chain needle guard should be less than 0.1
mm. (See Fig. 4). If necessary, adjust the clearance with screw "e" (See Fig. 4) and make
sure that th e gap bet ween chain needle gua rd and the tip of chain loope r is set at
1.0 2.0 mm. (See Fig. 5).
~
Note: Make sure th at th e chain needle "L0" is correctl y positione d behind the chain
looper in its motio n left to rig ht. The (L0) needl e ti p (motio n down) should be
positioned at the beginning of the chain looper hump (back of chain looper). See
chain looper o rbital motion on Fig.3.
11b