Juki 1541S Lose Stitches

[Wizcrafts]

If a #20 needle breaks and she isn't pulling hard on the material, then needle deflection caused by thread tension is a possible cause. Reducing both top and bobbin tensions, rebalancing the position of the knots, should help alleviate this deflection. Also, check the feed dog and make sure it is not moving at a different rate than the needle. The Juki may be equipped with an adjustable rate feed dog control, used to ruffle curtains. This would be a bad setting for flat work.

If she is trying to force the work around the turns, the needle may be deflected into the feed dog surface.

If she has to move up to a bigger needle,she may have do the same with the thread. Otherwise there will be huge holes with tiny thread. The normal needle-thread combinations for upholstery grade walking foot machines are as follows.

• #69 thread: #18/110 needle
• #92 thread: #20/125 needle
• #138 thread: #23/160 needle

Edited September 22, 2015 by Wizcrafts

[Art]

A lot of times, breaking a needle is a result of crashing it into a feed dog or needle plate. Like Wiz says, easy to do when sewing a rounded corner. When you break a needle, you should recover ALL if it. There is some chance it can get down into the bobbin and/or hook and score-up the race. Get a little magnet (all sorts of that stuff from Harbor Freight) pen or pointer thingy, might be called a part retriever. Also, when sewing-in welts around a corner, make sure the welt foot has the back cut out to the left (or whatever way you are sewing) or the cord will make it want to go straight (and possibly push the needle into the dog). On tiny cords it is not much of a problem, but on the big stuff, if the back of the foot is not cut, it's like riding the monorail at Disney World. Also, if you are going to be doing boating canvaswork (not much canvas anymore, sunbrella now), Use Tenara thread or something else you can get in clear, that way you don't have to stock a bunch of colors; and yes Tenara is THAT expensive, so learn to sew and use your machine first.

Art

[KelseyR89]

If a #20 needle breaks and she isn't pulling hard on the material, then needle deflection caused by thread tension is a possible cause. Reducing both top and bobbin tensions, rebalancing the position of the knots, should help alleviate this deflection. Also, check the feed dog and make sure it is not moving at a different rate than the needle. The Juki may be equipped with an adjustable rate feed dog control, used to ruffle curtains. This would be a bad setting for flat work.

If she is trying to force the work around the turns, the needle may be deflected into the feed dog surface.

If she has to move up to a bigger needle,she may have do the same with the thread. Otherwise there will be huge holes with tiny thread. The normal needle-thread combinations for upholstery grade walking foot machines are as follows.

• #69 thread: #18/110 needle
• #92 thread: #20/125 needle
• #138 thread: #23/160 needle

Hey Wizcrafts!

Was wondering if you'd be able to help me with something that I haven't been able to find an answer for. On my searches you replied to many people with very helpful answers so I'm hoping you could help me out too I recently bought my first sewing machine, a Seiko STH-8BLD-3 and after much work have finally got the tension right. However, I've noticed all along that the beginning and ending stitches aren't super tight and I can somewhat lightly pull on the thread after cutting it and the stitches will pop right out! I'm not sure if this is related to the tension (I have the tension the best it's been yet and the stitches are still popping out) or if I'm doing something wrong.

I've been doing 2 back stitches starting and beginning, but even then it doesn't matter because as soon as you pull the thread it pops out. If there's any advice you could give I'd appreciate it! I am so ready to start using this for my products

Thank you!

[Wizcrafts]

Kelsey;

Try backstitching three stitches and hold both threads taut as you do so, until you pass the starting stitch. Make sure that the knots are as centered inside the material as is possible. Finally, use a smaller needle if all your stitches are loose (experiment).

The travel of the check spring has an influence on the stitch tightness. Longer travel makes for tighter stitches all around. But, too much travel can dissolve the loops before the hook picks them off.

[stickandtin]

Wizcrafts-

Took your advice about checking top and bottom tensions on the 1541S. Backed off both, then started tightening both a little at a time. After each tightening, I would run about 3 inches of test stitches on two layers of scrap marine vinyl. I could see improvement in the tightness of the stitches after each adjustment and test run. After the 12 test run, I felt the stitches looked like they were where they should be. I then doubled the marine vinyl over again so there were four layers. Ran it through the machine and stitches looked great top and bottom. Wife then started sewing seat covers out of the marine vinyl for chrome dinette chairs. After about ten minutes of sewing I checked stitches. Now there is intermittent tiny balloons on the bottom. Machine will stitch tight, then she'll get about an inch or more of tiny balloons on bottom, then tight stitches again. Doesn't matter if it is around a corner or on straight run. Do you have any idea why the machine is doing this? Thanks.

[stickandtin]

I should add that she is sewing piping using the correct size piping foot into these chair covers. She made the piping using plastic welt cord and covering it with marine vinyl. So in essence she is sewing through 4 layers of marine vinyl. She is using a #20 needle and #69 thread.

[Wizcrafts]

The intermittent "tiny balloons" on the bottom would be thread knots or even top thread loops on the bottom. There would be two things that would account for this.

1. The top thread is twisting up in the upper tension disks, out of the primary pressure zone, causing it to lose tension
2. The bobbin was wound incorrectly, or is warped and is binding intermittently

Check the spool of thread to see if it comes off the spool like a coil spring. If so, place a funnel on top of the spool and feed the thread through the spout, up to the thread guise on the stand. Then, when it gets to the three hole thread guide near the top tensioner, go through all three using a wrap around technique. This may counteract the twisty thread.

The opposite can happen if the bonding on the thread is sticky in some areas and loose in others. Examine the cone and see if the thread sticks too much intermittently.

Wind a fresh bobbin load, using a fairly strong amount of tension on the disks on the far end of the winder assembly. You want the bobbins to be loaded tightly and evenly all the way across. As the bobbin is loading, check it for out of roundness. If the sides are bent the booin may bind inside the bobbin case.

Check the bobbin case tension spring and slot for thread pollution. A ratted piece of thread can cause intermittent tension changes. You don't need a lot of bobbin tension. Use just enough to get a decent lay on the bottom, with the knots buried between the layers. Then you won't need as much top tension either.

Finally, make sure that the top thread is feeding through the check spring and adjust its travel to see if it makes any improvement, or worsens the issue. The adjustment should be set bey a little screw in a curved slot on the disk facing forward, over the check spring. One direction lengthens the travel and vice-versa.

[stickandtin]

Thanks wizcrafts. Boy this machine sure is sensitive. But when it's on, it is incredible. Do you think the #69 thread is too light for 4 layers of marine vinyl? Should she go up to #92?

[Wizcrafts]

Thanks wizcrafts. Boy this machine sure is sensitive. But when it's on, it is incredible. Do you think the #69 thread is too light for 4 layers of marine vinyl? Should she go up to #92?

Sure. #92 thread has 15 pounds test, as opposed to only 11 for #69 thread. If you do that, use #20 round point needles.

[stickandtin]

Ok, she'll give it a try see how it works. Thanks for all the tips.