Upper Thread Is Twisting.

[Tom Spivak]

Hi guys, I just got my shipment of threads from the thread exchange and thought I'd be set up.

I'm running a Mitsubishi LU2-4400 walking foot machine and I just put a sew quite 5000 with needle positioner on it (which by the way isn't working) and got myself set up with a 140 leather needle and 138 nylon thread.

The problem I'm having is that after running a foot or two, and it's not consistent, the upper thread twists tight until it forms a ball and breaks off at the needle.

I have checked the threading over and over, needle is in correct as far as I can tell , groove to left,

I was trying this on two layer soft upholstery leather maybe 3/16 total, and two layers vinyl.

What should I check next?

[Sovran81]

Is the thread pulling off the top of the spool or unwinding from the side of the spool?

[Tom Spivak]

Off the top.

[Tree Reaper]

Any idea what your top tension is, I'm running at about 12 oz., a little over 1/2 lb.

You could probably step up one needle size.

[dirtclod]

I've had the same problem with nylon thread except mine wadded up on the top post or would wad up on the upper guide on the thread stand and would mess things up. What i wound up doing was put a piece of panty hose on the spool enough to cover the whole thing.

What you have run into is one reason i WON"T use nylon thread if i can get poloyester thread in the right color, plus i think nylon is hard on your machine.

Edited April 6, 2014 by dirtclod

[gottaknow]

Any thread that is unbalanced (over twisted) will cause issues. Some brands are worse than others, as well as darker colors. I've had polyester thread behave the same way as well as polyester core/cotton wrap which is a very common garment thread. Inexpensive thread will usually have more issues. When we use nylon, we always use A&E thread. Their quality control is really decent.

When you have to use unbalanced thread, you have to control it all the way from the cone to the tension disc. After that, there's not much room to deal with it. First I'll leave the original plastic bag over the cone with just a small hole at the top to feed it through. You can also buy an additional set of thread guides that you can clamp to your thread stand. Take some extra wraps wherever you can. I also keep a supply of small coffee stir straws on hand and will place these along the thread path, running the thread through them. You can experiment where they work the best. The idea is to prevent the thread from winding around itself. You can also take a wrap around the needle itself which make it flow better through the eye.

Lastly, try different brands of thread until you find one that works well for you. Thread is as critical as the leather you're sewing as far as quality goes. In a factory, imagine having to deal with your one machine with lousy thread 100X. Not fun.

Regards, Eric

[Dwight]

Off the top.

^ ^ ^ ^ ^ ^ ^ ^ ^

THAT is you problem. Bend the thread arm down so the thread is pulling from approximately the center of the spool, . . . and make it turn the spool as it pulls it off.

I learned that a long time ago with my machine doing belts.

May God bless,

Dwight

Edited April 6, 2014 by Dwight

[Tom Spivak]

I try any or all these solutions one at a time and see what happens.

If I get a change I'll report back.

[Tom Spivak]

So I took an extra turn through the first set of thread guides , revisited the threading diagram ,which sucks by the way, and found it needed to go through an almost indistinguishable guide closer to the needle, and one of the guides is missing completely but i don't think that one is imperative to operation.

Also, just because I'm stubborn, I changed to black thread.

Success!

And I went from two layers of vinyl to two layers of what I would think would be like heavy boot leather, hard and 1/4 total with what I would think was a perfect stitch and had to make no adjustments.

Only thing I noticed was a indent from the inside foot.

In fact I think the stitch on the leather looks better because with the vinyl I was have trouble getting the top thread to be in the center, it wanted to be at the bottom.

Maybe with the vinyl I need to gone done a thread thickness and needle?

On the thinner leather it looks fine.

[leatheroo]

I had this problem.....i had the needle facing the wrong way!!!