Thread unravels on old Pfaff 145-6-40D

[Davidstryingtosew]

I'm having a problem with this older machine. As in the title, my top thread keeps building up right at the needle eye.
 I changed needles, thread, material. I adjusted the tensions but I cant seem to stop this machine from unraveling the top thread.
The spring that helps the take up lever is kind of binding, a little. It moves freely up and down, but it isn't resting all the way down. I have messed with it some, but it really doesn't seem to be related to this problem. I know quite a bit about these machines.. but no where near as much as you guys here in this forum. So I was hoping for some guidance... please

David Miller

[brmax]

Yes, it looks all jacked up even before the guide at the needle bar, Comparing to the bobbin thread also in photo.

Floyd

Edited December 6, 2016 by brmax

[Davidstryingtosew]

It does sew for a while before this happens.
 It was much worse. I messed around with it for a while and got it tosew longer, but it still happens. Could it be that I'm using the wrong twist thread? I don't know.

[Hockeymender]

Make certain the thread is properly placed between the tension discs and is staying there. I had an issue with a machine where the thread would "pop" out of the discs while I was sewing and create a similar mess. Also, check that the thread is feeding off the spool without binding or sticking of any kind. 

[Davidstryingtosew]

So what your saying is that it may be caused by intermittent changes in tension?

I will give this a try.

I did notice the thread whip (?) after the take up lever change a little bit when ever this happens.

Seems quite touchy if this is the problem. Maybe the spring just before the take up lever is the issue as well. It doesn't respond as my other machines do.

I will start with your suggestion Joe and take a very close look at the spool and disc.

 

Thanks!

David

[Uwe]

Also check for burrs and other rough edges (needle, feed dog, hook etc.) that might fray the thread, especially if you installed new presser feet or feed dog recently.

A new needle is always a good idea when you have thread trouble, perhaps one size up. Make sure the thread slides easily through the eye of the needle.

If you found the thread in a bargain bin, check for proper twist as shown in EVERY Singer user manual:

 

Turn a few stitches over by hand and watch the thread up close. Often you can see where things go wrong when you do slow stitches.

That thread check spring should move freely and rest on the edge of the adjusting blade. Perhaps the thumb screw is too tight or front of the check the spring is caught under it? This shouldn't fray the thread but it's good to fix it anyways.

 

Edited December 7, 2016 by Uwe

[Darren Brosowski]

A few things cause this on machines.

1/ always make sure you have the correct needle

2/ check the needle plate for any roughness on the top and bottom edges.

3/ run your finger around the edge of the shuttle to check for any burs.

4/ If it is a horizontal shuttle there is an arm in front of the shuttle that opens to let the thread through. Ensure it is open enough for your thread and check for burrs.

5/ The timing could be out by a fraction.

Also try different thread as the sewing machine fairies sometimes cause problems with one specific thread type LOL

If thread is old then toss it away

 

 

[brmax]

Might be able to see something else with a new photo with tension area and guides possibly.

By the way what size thread and such. I am a bit more curious with the thread path top side.

The take up spring should set against the stop unless in a bind, though it looks clean on the front side, it may require a re adjustment.

good luck there

Floyd

[Davidstryingtosew]

You guys are amazing. I figured on waiting a few days to a week for some replies and I come back to my computer just hours later to find all guys taking the time to help me. Thanks!!

 

Everything that had been mentioned has been looked over. Nice to see I did look into the right direction.

The thread isn't really fraying, every strand stays intact. It seems to be unraveling. I only have left twist thread and that's all my other machines have ever needed. I have never ran into a machine old enough to need right twist, so I don't know what differs in those machines.

I haven't had a chance to play with it since my last response, but I'll be able to this morning. First need a nice hot cup of coffee.

I'll also get more pics uploaded

[Davidstryingtosew]

Well I did figure it all out. The one thing I thought wouldn't matter seems have been the culprit. That dang little take up spring. I loosened it just a little and "Snap", it fell right into place. I ran the machine in forward and reverse nonstop for about 4 feet at least, no frayed thread. I feel embarrassed, happy and relived all at the same time. I love these Pfaff Machines. I'm working on a complete restoration of an H4 model. I just wish they had the M bobbin like the Juki.

Here's some pictures 

[TinkerTailor]

That post on the top of the machine the thread travels through is more than just a thread guide, and ir should have holes at 90 degrees to each other. I have heard some of the old school dealers on here advise people who have thread twist problems to run it through one hole, around the post 90degrees, and then through the other post. Something about doing this counteracts the twisting.