If it has been a while since the needle has been changed, doing so may be helpful. Also be sure to use a sharp needle that will more easily penetrate the zipper tape.
Be sure that you are actually lowering the presser foot before stitching (this most likely isn't the case--just a thought).
Most machines also have a presser foot pressure adjustment that can be loosened or tightened to accommodate different thickness of fabric and the amount of pressure applied by the zipper foot on the fabric and the feed dogs. Experimenting with that pressure adjustment may be helpful.
Some bobbin cases also have a finger extension with a hole through it. If you are experiencing issues with bobbin tension, sometimes threading the bobbin thread through that finger will help even out bobbin tension.
Using lighter weight thread will also affect the resulting thread tension. If the bobbin case is wound with light weight thread, the bobbin tension will not operate the same as it would with standard weight thread. Light weight thread in the bobbin will cause looser tension, but heavier thread will cause a tighter tension.
Technicians use a standard weight thread to test tension on a machine, but if you use a different weight thread, then your results most likely will not be the same.
Bobbin Tension How and Why Tension is AdjustedHow can properly adjust my tensionUnderstanding Thread Tension Threadshttps://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=12&cad=rja&uact=8&ved=0ahUKEwiBnuWi4tnLAhXBtIMKHRRPA5gQFghPMAs&url=http%3A%2F%2Fwww.ca.uky.edu%2FHES%2Ffcs%2FFACTSHTS%2FCT-MMB-213.pdf&usg=AFQjCNE4QlGk1Fvt8K2UGCRCfzMpGS-A2Q
Most tension adjustments can be accomplished via the upper tension. However, there are times when the bobbin needs to be adjusted. Sewists are frequently nervous about adjusting bobbin tension. It is important to mark with permanent marker where the skrew-slot is positioned on the bobbin case BEFORE attempting any adjustments (at least if you need to return it to the original setting, you'll know where it was). Make only 1/8 turn adjustments at a time and re-test. (Righty-tighty, Lefty-loosey!) Sewists who frequently use different weight threads in their machine will often have an extra bobbin case that is set up specifically for that thread weight so they don't have to manipulate the bobbin case every time a thread is changed.
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Consult your owner's manual. The troubleshooting section will usually list error codes and how to correct them.
If the error code is not listed in the manual, you may want to contact a Juki technician for advice.
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hello there
at normal case needle bar must be in upper position because DDL-8700/7 does not equipped with needle feed. for your problem please check back tack solenoid open and close when you make back tack ( sometimes it was jammed and need to move by hand ).
best regards
ashraf abozid
Cairo - Egypt
[email protected]
try using a pair of tweezers to get the ends of the thread
while pulling the thread manually turn the machine backwards so that the thread unwinds as you pull it out
other than that you may have to take it in for a service where the mechanic can remove items to get the thread out
that service may not be covered by warranty but that will depend on the mechanics attitude to wanting your business
hello
regarding error E730 only two way to resolve :
1- check connectors between motor and control box.
2- need to replace AC servo motor ( encoder was damaged )
best regards
ASHRAF ABOZID
[email protected]
Cairo - Egypt
1. Remove the needle and bobbin assemble completely.
2 Try to move the hand wheel - forcefully if necessary.
3. Place one drop of oil on race. That is the little dip that has been circled. The hook (pointed thing) must ride on this smoothly.
4. Try to move the hand wheel again. Back and forth until it will move without resistance.
5. Oil parts that move with metal against metal.
6. Replace the bobbin assembly. Try to rotate the hand wheel again. If it is ok you can replace the needle.
7. Try to rotate again. If it rotates smoothly you shouldn't have any further problems. If the needle strikes something under the throat plate you will need to get the sewing machine timed.
E007 error code is for motor overload condition. Check to see whether you have thread entangled in the motor pulley, check also that there is no resistance when turning the motor by hand.
Check the motor output connector (4P) for connection or disconnection problems.
hi
it's easy don't worry about that , just try to move needle to left and right before start to remove broken scrw, you can catch needle by and spanner. second after removed needle by pull it down ( it's not so easy to remove but try also by spanner. just bring any needle with thick size ( 18 or 23 ) and try slowly move the broken scrw to counterclockwise direction . it will takes long time but at final broken scrw will out of needle bar.
best regards
ASHRAF ABOZID
CAIRO - EGYPT
[email protected]
Refer to your instruction manual on Page 22, the reverse stitching control buttons are on the extreme upper left and the one below it.
To start the reverse stitching press the upper left button and to revert to forward stitching, press the second left button below it.
HI there
can you please inform us what's model of control box? there is no error named E815 !!!! please we need more explain to help you.
thanks and best regards
ASHRAF
CAIRO - EGYPT
[email protected]
1. The bobbin carrier is moving (needs adjustment on the left and right to keep it from moving.
2. (Most likely problem). The timing needs to be adjusted. Give it a try or get your repairman to do it. See 19. Needle To Hook Relationship.
hi there
regarding your inquiry about JUKI machine model DDL-8700 , first your machine type was what ? DDL-8700/SS ( for light to medium material , DDL-8700/HS ( for jeans and can use to sew light to medium lather, type of needle is DBx1, size for lather was 18 and you can use thread number #30 and #20. one more thing you want to change your presser foot to teflon presser foot ( please see attached photo for that presser foot you want to buy.
if need more information please ask
thanks and best regards
ASHRAF ABOZID
CAIRO - EGYPT
[email protected]
Hello Lacinda have a good day to you concern loose or missed stitches please check next: 1-try to change bobbin case with new one. 2-check timing between needle and hook by -make needle bar at lowest position and you can see two mark line at needle bar. -bring the needle bar at second line from down side then check the flat part from needle comes with tip of hook ( if yes means timing is OK , if not means you need to adjust the hook timing . 3-check the ginger guide for hook try to move it foreword or backward to pass thread smoothly. if this is helpful OK if not please send email, i try to do the best to help. best regards ASHRAF ABOZID CAIRO - EGYPT [email protected]
