consew 206RB-5 thread tension issue

[alpine luddite]

I'm looking for some suggestions to get my machine's tension sorted. I use it 10-20 hours a week and it's normaly fine. But today the tension is acting funny. the stiching looks fine on top and bottom, but then I'll loose tension on the bottom and have a bunch of looped thread.

 

i have checked the bobbin tension, the top tension, changed the needle...looking for more suggestions.

 

thanks

[Pintodeluxe]

I had a similar issue with a 206RB-1 a week or two ago.  My bobbin thread was unusually hard to pull, and didn't respond to tension adjustments.  I replaced the bobbin, and adjusted it for light tension, and it solved the problem.  

How does the bobbin tension feel?  Is it tight?

[alpine luddite]

13 minutes ago, Pintodeluxe said:

I had a similar issue with a 206RB-1 a week or two ago.  My bobbin thread was unusually hard to pull, and didn't respond to tension adjustments.  I replaced the bobbin, and adjusted it for light tension, and it solved the problem.  

How does the bobbin tension feel?  Is it tight?

it feels ok. i just switched out to a new case and adjusted the tension. the loops are actually the top thread. it randomly goes out of tension. the loops in the photo are the top thread, looking at the bottom of the fabric.

[Uwe]

Closely inspect your top thread path,  or better yet, pull out the top thread and thread it again perfectly. 

Edited October 19, 2017 by Uwe

[alpine luddite]

20 minutes ago, Uwe said:

Closely inspect your top thread path,  or better yet, pull out the top thread a thread it again perfectly. 

I'll try that again. thanks for the help.

 

nice website. do those Pfaff 145 have reverse?

[Wizcrafts]

I appears to me that the top thread is changing tension as you sew. This can be caused by any of the following causes.

1. Twisty thread on the spool, feeding like a coil spring. This causes the thread to lift inside the tension disks, or wrap around posts and guides, or even the bottom of the spool itself. If this is the case, either wrap a nylon stocking, or thread sock around the spool, or replace it with better thread.
2. Thread feeding into the top tension disks is fed to high up, allowing the thread to lift up out of the center pressure area. Wrap the thread around the leading thread guide (before top tensioner) and feed it out of the lowest hole. If the guide is sew inline with the top of the machine, loosen its set screw and turn it perpendicular to the tensioner. This will line up the holes vertically, with at least one near the bottom of the tensioner disks.
3. You forgot to feed the thread through something important, like the check spring, or take-up lever.

If there is nothing wrong with the top thread or its path, the issue must be in the bobbin, bobbin case, or shuttle, or in the timing. Check the tension on the bobbin thread. It should be easy to pull and come out smoothly. There are good and bad bobbins, as well as properly and improperly wound bobbins.

[ljk]

All good advice.  Check upper tension discs for grooves.  I use 600 grit sand paper with a little

oil on a piece of glass.  Sand till smooth. Also hold bobbin case tension with right fingernail

lift slightly and blow clean. 

[Uwe]

1 hour ago, alpine luddite said:

nice website. do those Pfaff 145 have reverse?

Thanks and yes, the Pfaff 145 has reverse. 

[alpine luddite]

1 hour ago, Wizcrafts said:

I appears to me that the top thread is changing tension as you sew. This can be caused by any of the following causes.

1. Twisty thread on the spool, feeding like a coil spring. This causes the thread to lift inside the tension disks, or wrap around posts and guides, or even the bottom of the spool itself. If this is the case, either wrap a nylon stocking, or thread sock around the spool, or replace it with better thread.
2. Thread feeding into the top tension disks is fed to high up, allowing the thread to lift up out of the center pressure area. Wrap the thread around the leading thread guide (before top tensioner) and feed it out of the lowest hole. If the guide is sew inline with the top of the machine, loosen its set screw and turn it perpendicular to the tensioner. This will line up the holes vertically, with at least one near the bottom of the tensioner disks.
3. You forgot to feed the thread through something important, like the check spring, or take-up lever.

If there is nothing wrong with the top thread or its path, the issue must be in the bobbin, bobbin case, or shuttle, or in the timing. Check the tension on the bobbin thread. It should be easy to pull and come out smoothly. There are good and bad bobbins, as well as properly and improperly wound bobbins.

Thanks for that.  I really appreciate it. the closet industrial sewing machine repair is in Denver or salt Lake, both 6 hours away.

It seems the thread is falling out of the lower tension/spring disk.  is the "hook part of the tension disk in the correct location on my machine?

[Uwe]

You have to pull the thread up past the little hook on the check spring unit. 

 

[JimF350]

I have a new tension plate for my Consew 226, but the 2 sets of plates are not in line, they are offset. is this correct for my machine, the thread will not stay in the spring tensioner.