Timing if upper and lower loopers

Without the knife in place once fabric is moving through the serger, it can easily drift too far into the moving upper and lower loopers. ... Solution: If the fabric edge is not to be cut, simply guide the fabric edge next to the cutting knife.
https://www.heirloomcreations.net/the-taming-of-the-serger/

I don't know your model in particular but generally this is how you set up a serger/overlocker to create a rolled hem. Remove the left hand needle and thread if 4 threads are threaded). Now there is usually a lever around the stitching area that you slide back towards you to remove the stitching finger back (disengaged). Then you adjust the top looper tension looser (about 2-3) and lower looper tension tighter (7 or 8). Leave needle tension at normal tension (5). You may need to move the cutting blade to the right too. The technique is to cut the fabric wider but with a narrow stitch so the cut edge rolls under within the stitching. You want the top looper thread really loose so it rolls right around underneath up against the needle thread, the lower looper thread needs to be tight and almost invisible, pulling the upper looper thread down. I usually do a few test runs and check the stitching. Once happy, I turn the stitch length right down to 1 so it is very dense. This uses a lot of thread up.

Ideally use a wooly overlock thread on the upper looper as this "fluffs" out once stitched and "fills" in covering the fabric edge completely.
some good images here
Sewing Basics Narrow Rolled Hems with Serger Sew Mama Sew Outstanding...

you have to make sure the looper is properly positioned. With the screw loosened slightly you should be able to move the looper up and down slightly, thus adjusting the timing. You are looking for the lower looper tip to come in slightly above the needle eyes, as close as possible without touching. Then the upper looper must come in right behind the lower looper "head" as close as possible without touching. The upper looper should then extend past the left needle by about 2-2.5mm, and the needles will come down before the eye of the upper looper returns to the right.

here is a video

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

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 www.sewing.about.com, just search "overlocker" to find the specific pages.


Good luck

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.

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

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.

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