JUKI 563 thread snagging on bobbin case

[Gregg From Keystone Sewing]

BTW tell matcanada to give you your bobbin case opening lever back.  

[mikesc]

Gregg ..re "the gap" .my 211 sews beautifully with the gap set at 1.5mm, ( threads from 45 to 138 ) , however , if I set it to "manual specs"( as per your posted diagram )..it is not happy at all , and does what the OP's machine does"..."hangs on the basket sometimes"...hence my suggestion..

[matcanada]

You guys are really amazing! I retimed the machine, but the resulting change was very minor, so I doubt that was the problem. Increasing the gap with respect to the bobbin case opener to 1.5mm seems to caused more of an improvement. I'm trying to order some new bobbins and a bobbin case opener directly from JUKI which hopefully will resolve the problem entirely. I expect them to get back to me within the next couple of days.

[matcanada]

After a longer wait then expected (there is a late summer construction holiday in Quebec for two weeks), I received a new JUKI bobbin case opener and a lot of JUKI bobbins. Unfortunately, the problem still persists with these new parts, although I think that it did reduce its frequency slightly. I've gotten to know the machine to the point that I can feel the snag coming, especially when working with the handwheel as there is suddenly much more resistance to turn the wheel and then the thread snags. Any further ideas on how to solve the issue?

[Wizcrafts]

12 hours ago, matcanada said:

I've gotten to know the machine to the point that I can feel the snag coming, especially when working with the handwheel as there is suddenly much more resistance to turn the wheel and then the thread snags. Any further ideas on how to solve the issue?

One suggestion is to replace the bobbin case and shuttle with a new part. The other is to add slack to the top thread by experimenting with the check spring tension, travel and screw position in the curved slot. You'd be surprised how much influence those settings can have on bobbin case vs top thread problems. This is especially true if the top thread is very tight going around the bobbin case. Adding slack relieves the tension and may allow the looser thread to avoid getting caught in the slit in the case.

[matcanada]

Thanks for all the great suggestions. I had a technician over the other day to look at the machine and he felt the problem was mostly that the bobbin case cover slide plate was slightly bent downwards towards the bobbin which put pressure on the thread as it passed around the bobbin case. He banged the cover plate so that it's now bending away from the bobbin and the machine seems to be working fine. He did also mention, as you said Wiz, that if that doesn't solve the problem, the whole bobbin case assembly would have to be replaced, but for now, everything appears to be working fine.

[mikesc]

It is amazing how some well placed "percussive maintenance" can solve seemingly intractable problems :)

[suzelle]

So much great information in this thread! I know it's an older post but much appreciated! I'm going to use all of it to try and fix same issues I'm having with my own machine. Mine is a different machine than the one here, but issues are same.

[ValJ]

I know this is an older post, but I hope this will still be seen. Tremendous amount of useful information that I will store away for my new to me Juki LU563. Thank you! I have listened carefully to the debate over the bobbins as that was what I was originally trying to decide,  order steel or aluminum. Perhaps more importantly regarding bobbins, where do you recommend purchasing some that are made with correct specs and top quality?  I have a head injury and I’m trying to get back to Sewing and some machine repair. It’s therapeutic when I don’t get frustrated over what I have forgotten because of the head injury.