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18. Thread Tension
ProperTension
Propertensionrequiresabalancebetweentheupperand
lowertensions.
Thetensionneedstobehighenoughtoallowthetake‐up
levertocompletethestitchwiththeupperandlowerthreads
drawnintothemiddleofthematerialbeingsewnbefore
additionalthreadcanbepulledfromthespoolorbobbin.
UppertensionTooHighinrelationtothelowertension
Asthetake‐upleverisrisingtofinishthestitch,thelower
threadunwindstoofreelyfromthebobbin.TheUpperthread
withdrawsentirelyfromthematerialstretchedtightacross
thetop,pullingthelowerthreadwithittothetopofthe
material.
Tocorrectthissituation:First,decreasetheuppertension.
Thenifnecessaryincreasethelowertension.
UppertensionTooLowinrelationtothelowertension
Asthetake‐upleverisrisingtofinishthestitch,insteadof
threadbeingdrawnfromthebobbintofinishthestitch,
additionalthreadisunwoundfromthespoolbeforethe
lowerthreadisdrawnintothematerial.Thelowerthreadis
stretchedtightacrossthebottomandtheupperthreadis
drawndownthroughthematerial.
Tocorrectthissituation:First,increasetheuppertension.
Thenifnecessarydecreasethelowertension.
TheUserManualhasachartinsidethebackcoverwith
recommendationsforbothupperandlowertensionsettings
forvarioussewingoperations.RefertotheUserManualfor
thecompletechart.