Janome J30 - Page 4

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Condition Cause How to Fix Reference
3. Breaking 
 upper 
 thread.
1. Initial sewing speed is
 toofast.
2. Threadpathisincorrect.
3. Needleisbentordull.
4. Toptensionistoostrong.
5. Needlesizeisinappropriatefor 
 fabric.
6. Needleeyeisworn.
7. Needleholeinneedle plate is
 wornorburred.
Startwithmediumspeed.
Usetheproperthreadpath.
Replacewithanewneedle.
Adjusttoptensioncorrectly.
Useappropriateneedleforfabricand
threadinuse.
Changetheneedle.
Repairtheholeorreplacetheneedle
plate.
4. Breaking 
bobbin
 thread.
1.Bobbinholderisincorrectly
 threaded.
2.Toomuchthreadiswound 
 onthebobbin.
3.Lintisstuckinsidethebobbin 
 holder.
4.Threadqualityistoolow.
5.Threadisjammingaroundthe 
 bobbinholder.
Setthebobbinthreadcorrectly.
Adjustthepositionofbobbinwinder
stopper.
Cleanthebobbinholder.
Changetoahighqualitysewingthread.
Clearoutthejammingthread.
5. Needle
 breaks
1.Needleishittingtheneedleplate.
2.Needleisbentorworn.
3.Needleishittingthehook.
4.Fabricisbeingpulledtoostrongly
 whilesewing.
Seemechanicaladjustment“Needledrop
position”.
Changetheneedle.
Seemechanicaladjustment“Clearance
betweenneedleandtipoftherotary
hook”.
Guidethefabricgentlywhilesewing.
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