Prism99

Yes. What happens is that the invisible thread stretches more than regular thread. This is why you want to wind the bobbin slowly -- to keep the thread from stretching while the bobbin is being loaded. It's also a good idea to fill bobbins only 3/4ths full -- especially if you are using plastic bobbins, although I also do it with my metal bobbins. This is to ensure that the outer edge of the bobbin does not distort from the thread and create havoc when you go to sew.

sewbeadit

When they first came out with the nylon thread they recommended to not use it in the bobbin area because it could damage the machine. Is that not the case now?

Tom W

I use invisible poly thread in the bobbin on many occasions as it is much less stretchy compared to nylon. I don't think I've even used any nylon at all since good clear polys came out.

Prism99

It probably depends on the quality of the thread. When it first came out, nylon thread closely resembled fishing line. The type of nylon thread I use (YLI monofilament) is about .003mm diameter and about as fine as a fine strand of hair. I do think there are some sewing machines -- especially those with plastic bobbin cases in addition to plastic bobbins -- that might wear out faster from using a lot of nylon monofilament, but most machines (including vintage) can handle it just fine.

jmoore

is this happening all the time? are you piecing or FMQing when it happens? I have a 6600 and definitely need to adjust my top tension when changing sewing tasks.

donnajean

I use YLI Invisible thread for all my quilts. When filling a bobbin, you have to slow down so as not to compress the plastic bobbins to the bobbin winder. I don't try to fill the whole bobbin at one time. I don't have to do any tension adjustment, but do make the stitch slightly bigger.

quilterpurpledog

Never use nylon anymore! It was never satisfactory to start with because it stretched, messed up the machines and cut the fabric. I like to use Bottom Line thread from Superior to do the things I used to do with polyester monofilament thread. It is a fine polyester thread. I use it on top to stitch in the ditch to anchor my blocks before I do the decorative quilting. It disappears completely after I wash the quilt. I have mixed feelings about using it in the bobbin. It works quite well but I like my quilting to show on the back of the quilt.

institches33

I've always used the Superior invisible thread in the bobbin. No problems.

quiltingbuddy

This might be a dumb question but how do you make your bobbin winder slow down as many have said here?

wellphooey

I learned the hard way (2 trips for expensive repair) that if you are using invisible thread -- no matter the brand -- in the bobbin, and you have plastic bobbins, you absolutely have to wind the bobbin slowly -- like at half-speed -- and don't fill it all the way. Maybe half to 3/4 full. When going full speed, heat is generated on the threads which tightens everything up and the bobbin will seize to the bobbin winder spindle. I broke TWO bobbin mechanisms trying to get the bobbin off the spindle. Since slowing down and not totally filling the bobbin, no more problems. Hope this helps.