Adler 067 GK-373 tension problem (advanced)

[HardenGoods]

33 minutes ago, Trox said:

Hi, Yes s Uwe yours have just groves that makes it harder to get tight tension on thin threads. His is worn right true and would cause problems, I would have changed that bobbin house for a new one...You can get them aftermarket for a good price.. You could try to widen/make the hole round again with a small diamond round file or simmilar..But remember it has to be polished afterwards...Use a white ceramic thin stone.... 

At this point I will try anything to fix my tensions issues. Feels like I am down to the point where it's a parts problem. Perhaps I will try widening the hole very carefully and then polish off with a high grit stone as you suggest and if it doesn't work lean towards a new bobbin top case.. maybe throw in a new check spring too as they are cheap. Thanks for the link, that is a reasonable price!

[Uwe]

edited post repeating myself.

Edited August 23, 2018 by Uwe

[FrancoisLeather]

18 hours ago, Uwe said:

edited post repeating myself.

Not sure I know what you are saying. You already resolved someones issue in a different thread and don't want to repeat yourself? 

[Uwe]

I had typed an elaborate post and then realized that I had already said the same thing earlier in this topic. I can't delete my own post for some reason, so i just cleared out my own, superfluous post.

[Mark842]

Is this problem consistent with different leathers? I notice you said on scrap from the same leather as the project. I chased this problem for months using a specific Latigo. I adjusted everything thing six ways to Sunday and was going nuts. On someones advise I tried a piece of latigo from a different tannery. Problem went away never to happen again. It was the leather not the machine.

[HardenGoods]

On 2018-08-24 at 7:27 PM, Mark842 said:

Is this problem consistent with different leathers? I notice you said on scrap from the same leather as the project. I chased this problem for months using a specific Latigo. I adjusted everything thing six ways to Sunday and was going nuts. On someones advise I tried a piece of latigo from a different tannery. Problem went away never to happen again. It was the leather not the machine.

This problem appeared on many different kinds of leather but I can definitely see a particular tannery or batch playing hard to sew. I’m in the middle of figuring this one out I think. I’ve noticed my takeup lever ascending before the thread reaches the 3:00 position around the hook which creates some random/inconsistent resistance, in turn, altering tension randomly.

[Wellington]

Hello, all,

I have a problem with the upper tension on my Adler 67-GK373, as well – specifically, far too much upper tension no matter what I do. (I figured it would be better to post to this thread rather than open a new one, simply to make it easier for others to resolve upper thread tension issues in the same machine in the future. If moderators prefer I open a new thread, please let me know...) When I'm finished sewing a seam and want to remove the workpiece, the only way I can pull out the thread is by grabbing it below the takeup lever and dragging out enough slack to pull out the workpiece and cut off the threads.

The upper tension assembly on my machine has a lever that you press to release the tension to pull the workpiece out of the machine, but the lever doesn't release enough tension -- even when I raise the presser bar by hand, and hold it higher with the knee lever, and push the lever on the tension assembly, and try to pull, the thread breaks, usually at the needle. (This is with T90 thread. with a new #22 needle if memory serves... I can successfully pull 138 thread out (using a #24 needle), simply because it's stronger, but it's still HARD to pull, and probably requires 7-10 pounds of force to pull out the thread.)

I tried backing off on the spring tension all the way (even taking off the nut) and that made it a bit better but not much. I disassembled all the tension disk assemblies, degreased, de-varnished, cleaned and inspected. One of the disks on the right-hand spring-loaded tensioner had a tiny, barely visible scratch that might have been made by a grain of sand on the thread. The scratch was barely visible, but you could feel it with your thumbnail, so I polished it out by wet sanding with 400 grit and crocus cloth. I took the upper tension sheetmetal "plate" assembly off and cleaned everything I could reach with brake cleaner and compressed air. (By looking at the back of the assembly, you can see how the lever releases the tension on the bottom right disc assembly.)

There are no burrs or grooves that I can feel in the takeup lever or any of the tension disks, or the post on the top of the machine, around which the thread starts its path to the tension assembly. 

At this point, I'm stumped. Does anyone have any clues for me on what to look at? I've been around sewing machines for a few years now, though this is my first walking foot machine, so this is extremely frustrating to me...I know how to thread the machine and have all the basics covered, I believe, and I think I'm trying to pull the thread out at the right time, with the needle bar up and the takeup lever just beginning to move downward from TDC. (Please ignore the thread in my photos...I was just threading bobbin thread through the upper tension path to try pulling the thread back and forth to try to identify where the bottleneck is.) The machine seems to sew fine, but not being able to release the upper tension is driving me nuts! Thanks in advance for any hints.

W.

ETA: Does anyone know whether an aftermarket upper tension assembly from a Pfaff 145 will fit here? I see the ones on ebay look a lot like mine...Is there any kind of "standard" that these assemblies conform to, I hope I hope?

Edited November 18, 2019 by Wellington

[Wellington]

Just to update the thread from my last post:

I guess this machine has a slightly different upper tension setup than I'm accustomed to with home sewing machines. I believe Adler designed it so that upper tension wouldn't relax when the presser lifted to climb over big upholstery seams. Bottom line seems to be "you can't loosen it beyond what you can do by lifting the presser by hand or knee, and pushing on the lever just below and to the right of the tension disks, and PULLING." That, and/or pulling thread just below the takeup lever to get enough slack to cut off workpiece. 

In getting this new machine dialled in to use various threads from 69 to 138 (haven't tried 207 yet), I guess I'm also learning that adjusting bobbin spring tension is just standard operating procedure for these kinds of machines – something I'm not accustomed to with my 201 or 130. 

With a lot of fiddling and learning along the way, I'm now getting good stitches and learning to live with dragging work out with my feet...so I'm pleased with machine. Reverse stitches don't match forward, especially on long stitches, but I can live with that, too. If backstitch needs to be same length, I can just turn the workpiece or back up a couple of stitches and go over again.

Bought a couple of new feet for it, and really looking forward to putting it to work. Sorry for the dumb newbie questions ... I'm sure I'll have more!

Edited November 26, 2019 by Wellington

[Bert51]

I was to9ld by a friend when I brought my first machine to find some scrap and practice, then each time you change thread practice. When you cut out a new project, before you start sewing get the scraps and pactice with so you know that your stitches are right before you put the needle into your project.

Every time I'm in a hurry and do not run some scrap first I get bitten.

Si I tell every one to practice.

Bert.

[ZIIK]

Hey Wellington, I believe it would be possible to make your machine release tension when you push/pull the release "button".

I believe something is either broken, missing or out of adjustment or specification in this case.

The button likely pushes on a plate that in turn push a thin rod through the tension unit. The rod push on a washer with a thin "bridge" across the center hole.

Putting pressure from the backside on this washer (the thin centerpiece) is what makes the spring back off to release the thread.

The length of the rod is important, and you can make your own if needed.

Remove your tension unit again and look at how the button linkage works. Try removing it and the rod. Then try pushing the spring with a thin piece of metal to make sure it moves (a scrap needle works in a pinch). Then you can probably figure out which part that is out of place or if the rod is to short.

I'm sure you can make it work. It is just more or less work.

Let me know if you require further assistance.