Problem with a Singer 112W139 Thread Controller

[tmitch]

I recently purchased a used Singer double needle 112W139.  I have a manual for the machine and have timed it successfully, I believe, but have a few problems I can't seem to solve.  First I can't get the thread controller to work properly.  No matter how I adjust it, it leaves too much slack.  I have moved the stop as low as it will go and turned the controller back and forth for tension.
Too much and it will not let the spring move to the top and too little and it not return to the bottom, and at the best compromise it leaves so much slack that the thread sometimes actually come out of the lowest guide just above the needle.  I have alternately thread it by the manual, and tried some of the "right way to thread a  double needle machine" found on the internet. Nothing seems to help.  I also have trouble with picking up the bobbin thread, but until I solve the slack in the upper thread, I don't want to tackle 2 problems at the same time. 

 

[Uwe]

You are probably talking about the check spring on your thread tension assembly. If by "turned the controller back and forth" you mean turning the little thumb screw nut on the check spring split post, that unfortunately is NOT where you adjust the tension for that spring. That thumb screw nut is more of a lock nut that holds the check spring discs in place.

Your check spring should be able to move freely.

Sometimes the spring gets caught under the thumb nut as you tighten it - that prevents the check spring from moving freely and operating properly.

Make sure your check spring moves freely and then see if your problem persists.

The tension of the check spring can be adjusted, it's just not obvious how it works.

I was motivated and made a video that hopefully explains how the check spring adjustment works:

 

[tmitch]

Thank you for the reply, but unfortunately or fortunately, I was doing it correctly.  So my original problems still stand.  I have moved the lower stop as far down as it will go, and turned the tension back and forth and as I said, too much tension and it won't reach high enough and too little and it won't return to the lower stop.  I have felt the spring movement and it seems to move freely.  I was unsure if the outer part of the spring belonged on the outside of the "disc" since I had taken all apart, but your excellent video clearly shows that I had reassembled it correctly.  In trying to get this machine working correctly I had to readjust the stitch length to match the numbers, which somehow, screwed my original timing, so I had to re time it again and now I think I have it just a little early but again, I want to solve this loose thread controller problem.  In all the videos I have watched of similar machine running, none of them seem to exhibit as much loose thread as I have.  Maybe that is not my problem.

I don't have enough strength to lift the machine straight up out of the hole in the table, as I don't yet have the female parts of the hinges so I have to keep calling my son every time I need to work on the underside of the machine.  I can't believe this thing is so heavy.  No wonder Singer called my old 306K a "featherweight".  

[Uwe]

Post a few close-up pictures or, better yet, a brief video of your threading path and what's wrong with your machine (ask your son to be cameraman for a moment.) There may be something else going on but it's hard to figure it out without seeing it.

[tmitch]

I'll try to do that (but I don't know how to attach a picture or video to a post), but something even more weird just happened.  When double checking my timing, I found the right hand hook assembly was almost 180 degrees off.  Thinking I had made a mistake, I corrected it and made sure the two hooks were in sync.  I then tried a couple of stitches which resulted in a rats nest under the stitch and a tangle of threads caught down in the machine.  I just got it untangled and unbelievably the right hook assembly is again 180 degrees off.  How can that happen?

[Uwe]

Each of the large hook gears has two set screws. One of those two set screws on each gear has to be sitting in the grove on the shaft. If neither of the set screws is in the groove the gear may rotate on the shaft as soon as the going gets tough and you have an instant mess on your hands. 

I recommend taking a break and a step back. Disconnect the belt until things are right again. You can do a lot of damage running a machine under motor power when things are not right.

Consider having a sewing machine mechanic put things back the way they're supposed to be. Then you have a clean starting point. It's hard enough getting a single needle machine to work right. A double needle machine is even more complex and not really an ideal candidate to learn the finer points of sewing machine maintenance on.

Also, have your son help you figure out how to attach pictures (look for the "Drag files here to attach" in the editing window.) You may also have to learn how to resize picture files so they're not too large to attach here. Without the ability to post pictures it will be nearly impossible to do proper remote tech support. We're all sitting in front of computers, not crystal balls.

 

Edited January 8, 2017 by Uwe

[tmitch]

First of all there are no sewing machine mechanics in the area (I wish there were).  I also realized that the hook gear set screws were not in the groove on the shaft, and have corrected that.

Here are a couple  pictures of the timing control:

As I turn over the hand wheel to make a couple of stitches, I get about 2 turns and the machine locks up with a tangled mess.  Here is a shot of the mess.

[Uwe]

With these style hooks (both single or double needle) you have to hold the threads taught for the first few stitches, otherwise you have good chance of things getting tangled up underneath, even on a perfectly adjusted machine. Here how I do it on a similar single needle machine:

 

[Uwe]

Also, on your threading path, it looks like you don't have the check spring threaded quite right. The thread needs to go up inside the channel past a little hook and then come back down towards the check spring. 

 

[brmax]

Its understandable that not many Sew machine mechanics, we just don't do the fabricating or manufacturing now days as our parents age group did many years ago.

I can say this site has been a great find for myself, both the group of people and their knowledge, but more important the ability many feel they are welcomed to share it.

On the machine I would take one of either side needle out with its specific thread top, bottom. Then move on in a complete setup as each saddle is separate, this seems to work on the non walker I have. What does come to mind and some can correct me to help out, some of these are timed at a certain stitch setting. Just something I recall

good day

Floyd

[tmitch]

Brmax, I live in a small Oklahoma town and we had sew machine repair shop a few years ago, but I guess he retired.

Uwe, actually I have the threading right as far as your video shows, but I still have more slack even with the large movement of the thread controller.  I will post a better picture below.  The trick of holding tension of the upper threads seems to have solved the binding up the rats nest down below. Now, I can work on the tensions of the upper threads.  Later today, I'll try to get my son to make a video of the slack left by the thread controller.

[brmax]

I'm not sure where the thread slack is your talking of, so I will say the take up spring at its adjustable rest position, ( the lower section part) should be very close to or at rest when the needle touch's the material or leather. This parts adjustment can some times change with say a consistent project but the most part can be set for your normal materials thickness.

Once the needle is in material the springs thread control is history! the way I see it anyway. So its on to another parts responsibility, but should mention the tension of "the take up spring controller" it self can be tweaked a bit before moving on and then maybe a follow up say after some of the regular tensioner adjustment proves your thread knots are in material center or close. 

So some of this is an option to do one side at a time, but all this you may already have done and so all is good.

 

Floyd

[tmitch]

Strangely enough, the large amount of slack below the thread controller seems to have gone away, so I locked down the controller setting.   I made a video, but I can't seem to make it small enough to attach it, but it just shows everything working right.  Thank god for this forum and for you, Uwe and Brmax.

[tmitch]

Still having trouble getting enough tension on the upper thread.  Has anybody used the "threading a double needle walking foot sewing machine the right way" by Moose Trading in witch he threads the two tension disks by going around the little posts (not what my manual says).  Here is what I am getting now on two layers of vinyl using the Moose Trading upper threading and I have the tension screws  pretty tight.

[Uwe]

One side of your stitch lines actually looks pretty evenly balanced.

Perhaps your bobbin tensions are adjusted too strong, and not quite evenly balanced. The top thread tension balance off the bottom tension(s).

Each bobbin case has a little tension spring to adjust the bobbin thread tension. Those screws are teeny tiny, short, fragile, and have a strong tendency to vanish. I use a screw driver for my eye glasses to adjust the bobbin thread tension screws a quarter turn at a time. 
Adjust the bobbin tensions so that they're very light, just noticable and about the same when you pull on the thread with just your fingers. 

[tmitch]

OK, I started over, setting my bobbin tensions very light and trying to get them even.  Then I backed off the upper thread tension and went back to threading like the manual directed (trying to thread them over the little posts was very difficult anyway).  My stitches look much better and more even now.  I think I am there now.  The only problem left is getting the threads to release from the hooks at the end of a stitch (I have to rock the hand wheel back and forth sometimes), but that might be just the nature of the beast.

[Uwe]

The best time to pull out your material at the end of a seam is when the thread take-up lever is at the very top. 

[brmax]

I couldn't find it for the world I'm sure, the video.  I will say some have the thread tension at a "very" lite tension and are able to just pull material away easily with no issue at all. Some times needle size or the thread hole has a lot to do with this also, and in textiles a bigger needle works just fine and can allow this without compromising the stitch hole

I haven't learned that yet with my equipment I wished, but to get going here, I seen a video of a dude doing some sewing and I did a re-wind, a few times at this vid point saying to myself ohhhh!

So with the thread lever guide up and the presser feet "still holding material down" take a finger and pull a bit of thread at left side of lever several inches. Your just making slack on the top side as bottom is held solid with presser feet down.

This gives you enough to pull material away and cut some thread much easier when you lift the presser feet, Its a trial and fit thing.

 

Good luck

Floyd

[Uwe]

If your thread tension release mechanism is working properly, lifting the presser feet will separate the top thread tension disks and it should be relatively easy to pull out the material (and thread.) 

[tmitch]

On 1/13/2017 at 0:20 PM, Uwe said:

If your thread tension release mechanism is working properly, lifting the presser feet will separate the top thread tension disks and it should be relatively easy to pull out the material (and thread.) 

Mine only releases at the "second" lifting position.