[Orly]

I have a single head SWF D-1201 wide frame. This has a frame size of about 39x39 so we often run jobs that go for 10+ hours...

Lately we've been having a baffling problem with the bobbin thread jumping out from under the tension spring on the bobbin case at completely random times. Sometimes it is right after a needle change, sometimes it is in mid-stitch. The bobbin thread comes right out of the groove and around to the top opening in the case. The result is that the machine continues to run with no tension on the bobbin and it gets pulled on top of the fabric. At first this was a freak occurrence but it has been happening more and more frequently, almost daily. Now I'm afraid to take my eyes off of the machine for fear of finding it has been stitching all bobbin for the last hour.

I've talked to several techs and they say it is either the bobbin is threaded wrong or the case is bad. They've never heard of this before and they think I'm nuts. I am positive I am threading the bobbin correctly, and I check the tension with a drop test at every bobbin change. I use pre-wound Coats and Madeira bobbins. I have tried two new bobbin cases, and it is still happening.

Could some other part be worn or damaged? Is it a timing/service issue?

[Robert Young]

Hi,

I have the same machine, but have never run into this issue before. I was just curious as to what you use yours for? (I know, not much help to your question, but so few out there have these machines compared to standard emb machines I just HAD to know, lol)

We use ours for embroidered art ( volantfineart.com ) as well as to produce custom fabrics for interior and fashion designers.

[Orly]

Aha! Yes, I've seen your site before. Nice to meet you. Great stuff, you guys do amazing work. We've actually considered contacting you about collaborating... We do fabrics for interior design - mainly produced on Schiffli equipment in Europe - but we use the SWF for developing patterns, sampling, and custom work. www.jenniferrobbinstextiles.com

For anyone still following the thread, I think I've solved the issue. That pigtail is actually on the bobbin case for a reason. Duh. It doesn't explain why my not threading through the pigtail wasn't a problem until the last month or so, but I'll be content if it just doesn't happen again.

[Robert Young]

How COOL is that! I love your site! Quite a "sample machine" you have, lol. This is my 20th year of digitizing and this is much more fun than corporate logo work was.

Funny how something so basic on the bobbin case can make such a difference. Hopefully the issue never happens again.

[ingeneren]

It is the bobbin not the machine. I no longer use the Coates and clark prewound bobbins for that same reason. I rarely use the paper back bobbins any more or the backless bobbins because they all tend to jump and I don' t need the down time. I switched to mostly NEBS plastic case prewound bobbins and have not had that problem since. If I have to use a paper back bobbin I will use Allstitch not Maderia or Coats.

The bobbin is too light and the thread tension is uneven which makes it skip. (I used to be a mechanical engineer before going into embroidery)