Question about Simplicity Frontier SL390 Mechanical Sewing Machine

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Timing if upper and lower loopers

I was sewing late and was trying to do a tight corner without cutting the fabric so I pushed the cutter away from me, and it jammed into the feed dog plate and stopped sewing. My husband opened up the compartment found that the upper looper was running into the lower looper preventing them to miss each other. Noticing that the lower looper was skinnier and curved behind its head he figured that the arms got thrown out of time and that the arms would just need to be adjusted manually to allow the arms to miss each other again. He loosened the upper and lower loopers at the hex screw on the respective drive shafts and was able to allow the arms to miss each other, but the threads would not chain properly so he tried to adjust them again. Now the threads will not chain at all. The arms seem stiff enough that they would not have been bent from the impact of the cutter and we are hoping that it is just a timing issue. How can we figure out the timing of all the parts so it will chain again?

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Re: Timing if upper and lower loopers

If you look closely at the components of the machine they should have small marks on them that line up with each other or marks on the case. most sewing machines are timed this way the marks have to be lined up on both arms and that should work.

Posted on Jan 14, 2008

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Pushing material away, but still overlocking

It is difficult to tell what exactly is happening with your serger.

First thing--make sure you RAISE the presser foot BEFORE you thread any of the threads. This releases the tension disks so the threads will seat properly. You may need to remove all the threads and rethread from the beginning, making sure you thread each in the proper order. Start out with the thread tensions set at the ideal setting--usually the halfway point between the high & low numbers. From there, you will adjust them to even up the thread tensions.

Are you actually trimming off some of the fabric as it is stitching? If so, you might try increasing the cutting width (moves the cutting edge further toward the right) so that there is more fabric caught within the looper threads. It also appears that the looper tensions may be too loose. Try tightening the upper and lower looper tensions so less of the thread loops don't fall off the fabric's raw edge.

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1 Answer

How do I adjust tension on a Janome Harmony 9102D

Sounds like you want to do a rolled hem for a handkerchief edge, I do the following to create a rolled hem on my over locker. Take out left needle and cut and remove that thread. Open front cover and slide back lever for the stitch finger in the needle plate, this finger stops the fabric rolling under thread tension normally so you need to pull it back out of engagement. Your Janome may have a similar means to select the rolled hem or you may need to remove the stitch finger with a screwdriver, it varies between models.

Thread upper looper with wooly nylon and right needle and lower looper in matching colour thread. (You can go wooly on the bottom looper but it hardly shows so I never bother.) Disengage upper blade and move the fixed lower blade to the right to trim less, then lower upper blade back into position. Now tension, needle leave alone (5)' upper looper very loose (2-3) and lower looper tighten up to 6-7 and test stitch. You want the upper looper thread to go right underneath and the lower looper thread to disappear against the needle stitch. And the fabric to roll inside the stitching. Finesse tensions on the loopers until this is right, you may need to change blade position too, depends on weight of the fabric and how it rolls. Once this is right turn stitch length down to close up stitching, 0.8 or even 0.5 if you want full coverage. Thats it. You can use differential feed if you want a fluted rolled edge, nice on knits.

Mar 02, 2015 | Janome Harmony 9102D Mechanical Sewing...

1 Answer

Upper looper hits lower looper

The upper/lower looper need realignment, requires a qualified technician to do this.

Oct 21, 2013 | Brother 1034D Serger Sewing Machine

1 Answer

I keep breaking my upper looper, what am I doing wrong?

it's possible that the fabric and the needles didn't
work togeather, the correct needles depend on what
fabric your sewing. could have been the tension
was too tight. or the needles could have been
bent or damaged at the point of the needle, I suggest changing the needle very often, sew on a
scrap piece of the fabric to see how the serger
reacts to the fabric, needle and the thread.
it could be a design flaw in the machine. or there is something wrong with the upper
looper adjustment or timing, if there is another
repair shop that you can go to , if there is I suggest going to it.
do you have a manual for the serger? if not send me
a comment and I'll see if I can find one for you.

Nov 14, 2012 | Sewing Machines

1 Answer

Correct settings for 804dsp serger to sew a sweater.

Are you wanting to use the serger to sew a hand knitted sweater together? or do you mean a sweat shirt knit or other knit fabric. If it is the first option, I'd say don't bother, as you can't do it with the blades working because it will cut your knitting and the wool will unravel in the seams.

If it is the second option then I would start with the following settings.

Four thread stitch, so both needles and the upper and lower loopers threaded. Set tension on all four dials to 5, stitch length to between 2 and 3, and differential on zero. Move the cutting blade over to the right for a wider seam. Now test stitch on some fabric scraps double layer and see what the seam is looking like.

Now you want to adjust a couple of things: firstly width of the seam. Is it the size you want? If you'd like it a little narrower, then adjust the cutting blade back a little to the left to narrow the seam slightly - just depends on the fabric weight. For example if it is a loose open weave like boucle you would want a wide seam to make sure it holds the fibres fully.

Now you can adjust the upper and lower loopers to get the thread wrapping around the edge looking nice. Look at the seam and the fabric inside it. Is it tunnelling and pulling up the fabric? if so, release tension on both loopers a half number to put more thread into the seam. Test stitch again and see if the loopers are meeting nicely on the cut edge of the fabric. Upper and lower looper threads should be meeting right on the cut edge so if this isn't happening and one showing on the other side, then tighten the looser one by half a number and test again.

If the threads are hanging off the edge then you have the choice of moving the blade to the right to cut less fabric off, or tightening up the looper tensions to pull in the thread.

That's it, hope this helps you to master your serger.

If you'd like some images and further explanations of other stitching you can do with your overlocker, then Debbie Coswell has some great information on line at, just search "overlocker" to find the specific pages.

Good luck

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1 Answer

What setting are the three threads set on for a rolled hem on a singer ultralock l4sh654 and what is the lever by the plate for?

Rolled hemming on any overlocker is usually achived the following way. Right hand needle only.
Blade over to the right usually to cut wider than normal but you can vary this to suit the fabric and stitch width you want.
Thread in this needle and the upper and lower loopers. If you can source any, use woolly overlock thread in the upper looper, this fluffs out when not tensioned and covers the fabric to give the look of solid stitching. Change upper looper tension to about 2 and lower looper tension to about 6 or 7.

The lever by the plate is usually to control the little stitch finger where the stitches are formed, move it backwards and it should move back towards you?? If this happens, then you want it in the retracted (towards you) position for rolled hemming so the stitching is much smaller and the fabric can roll. Normally this stitch finger holds the fabric firm for the loopers to form the stitch over for your normal 3 or 4 thread overlock.

Now test stitch and see how it looks. Tighten the lower looper thread so it lays right beside the needle on the underside. You may need to then tighten or loosen more the upper looper, you want the upper thread to wrap all the way around to the underneath against the lower looper thread and needle.

The cut edge of fabric should roll to underneath inside your seam. Once you've got this happening, turn the stitch length down to 0.5 or so to close it right up tight. This uses heaps of thread so I usually test everything else, then close it up at the end to minimise waste.

Hope this makes sense, good luck.

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2 Answers

Rolled hem or rolled edge

You need to disengage the cutting blade by openingfirstly opening the front and left hand side covers. pull on the larger of the two silver knobs and slide the red lever towards you. I'm not sure what the tension settings are, but I'm certain you need to reduce them a fair bit to aid in the rolling effect. I only use 3 threads when doing a rolled hem.
My description isn't too detailed but I hope it helps!

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4 Answers

Brother 1034D

I had the same problem with the blue thread- it would sew and inch then pop- mine worked wihtout breaking after I re threaded in this order: green, blue, red then yellow

Jun 08, 2008 | Brother 1034D Mechanical Sewing Machine

1 Answer

Machine not sewing

Make sure you have threaded the machine from right to left, it sounds like the needle thread is trapped under the lower looper thread and cannot form a stitch.........start the threading over from scratch like this:

  1. Lower Looper
  2. Upper Looper
  3. Left Needle
  4. Right Needle
Is there a diagram for how to thread on the inside of the door ?

Follow that slowly and carefully to make sure you have not missed any thread guides on the way, as each one needs to be followed through to ensure correct tension and thread progression.

If you are certain that all threaded correctly, did you have a fabric jam and pulled it loose ? If so, the timing may well be affected.

Post an update and we'll get this right.

Bargain Box

Feb 01, 2008 | Sewing Machines

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