Where can I buy an upper looper for overlocker

There are a lot of web sites & videos dealing with timing. Just search for "serger timing" or "overlocker timing."

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Did you thread in the proper order? Upper looper, lower looper, needles from right to left?

Overlockers require precision timing. Take it in and have it cleaned, adjusted and timed.

Overlockers and or Sergers are ALWAYS threaded the same way. Upper looper, Lower looper, right needle, left needle. If you have a model number for your Juki we might be able to find you more information.

The best way to figure out tension problems is to thread each thread in a different color so you can determine which thread is giving you problems.

These machines can be frustrating and EVERY time the thread breaks you MUST start the threading problem from the beginning... upper looper, lower looper, right needle left needle.

You can purchase a manual for this machine from the following link for $US14.99

http://www.sewingpartsonline.com/instruction-manual-simplicity-sl4300.aspx

I can't see it anywhere for free download unfortunately. But you may find that looking at a manual for another 4 thread overlocker may get you started. If you try this link http://www.singerco.com/accessories/instruction-manuals you can look at the free Singer downloads,
try this link for their 654 3/4 thread model http://www.singerco.com/uploads/download/555_14sh644_654-(e_s_f)-(new-led-version).pdf
it may give you some help now.

Essentially, to change the stitch width you can either move the lower fixed blade wider to cut less fabric or tighten up the upper and lower looper threads in order to close up the stitching.

Moving the blade usually means opening up the front cover door, putting pressure on the upper blade and swinging it up out of the way. Then you can adjust the lower blade, usally by turning a knob near to it. Sometimes this knob will be marked 1, 2, 3.

Adjusting the looper tensions is done by changing the tension dial settings for the thread needing adjusting. If its a standard four thread overlocker that produces a "marrow" seam it will have two needles and two loopers, upper and lower. Generally on most overlockers, the upper looper will be the second from right tension dial and lower looper will be right most tension dial - turn up one half number to tighten, or down one half number increment to loosen, then test stitch again. The needles shouldn't need adjusting too often.

I usually start with all tension dials on 5, test stitch, then adjust from there. Some fabrics will tunnel (pull in) if the seam is too wide so you need to either move the blade to the left and trim more fabric or loosen off the loopers. Or in the reverse, like you are getting, the threads will hang off the edge.

There is some good serger information on Debbis Cosgrove's pages www.sewing.about.com but if you have never used a serger, then getting the genuine manual is probably best.

Has it ever chained off since you bought it? If you purchased it second hand it is possible that the timing of the loopers is out and this will prevent a chain from forming.

However, I'll go through general overlocker/serger troubleshooting for threading up. The critical things are to thread it exactly as the diagram shows, some sergers have a diagram inside the front looper cover so its easy to refer to when you are working on the machine. Or use the manual diagram. There is a sequence you need to follow in threading up, usually upper looper, lower looper, then the needles. This is important. Then you pull all four threads under the raised pressure foot, lower the pressure foot, and start to stitch and hopefully a chain forms. If you need to change a thread you can knot on a new colour, turn the tension to zero, then pull through the new thread. Pull the knot right through the looper eyes but you will need to cut the knot out and thread the needles with the new colour once you get there. Then turn tension back to the normal setting (5 usually) and again pull all threads under the foot.

The timing of the two loopers to the needles is critical to a stitch forming though so if you have tried everything and aren't getting a result; then perhaps its time to take it to a service centre, get it checked out and if it works fine for them, ask for a quick demo of threading up, then do it yourself with the demonstrator watching.

Overlockers are very different to sewing machines and there is a learning curve but once mastered, they are so quick and give a great finish.

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.

Then it's one of two things. First try setting your lower looper tension on 3 and see if that works. If not set it back on 4 and cut ALL your threads and re-thread the machine STARTING with the UPPER looper, then the lower looper, then the right needle, last the left needle if you're sewing a 4 thread overlock stitch. Make sure the threads aren't twisted in the thread guide. Make sure the lower looper thread is OVER the elbow on the upper looper and over the upper looper thread. Let me know if this works. We'll work until we get it fixed!

From what I have read this manual is less than desirable. Neither is the one for the brand that I have.

You may have better guidance if you purchase and use Nancy Zieman's "Serge with Confidence". I have found it very helpful.

For the two thread rolled hem, the looper cover is used to "trick" the looper into "thinking" it is threaded.

On my serger (not a Bernina), this is referred to as a "subsidiary looper". It is a spring type mechanism that fits in a small hole at the top of the upper looper.

You use a rolled edge presser foot; right or left needle; stitch length @ normal or wider; stitch length @ 1mm for the left needle/0.5 for the right needle; differential feed @ normal; needle tension - tighten; lower looper tension - normal or looser; two thread looper cover - engaged.

Test and adjust the tension as needed before making the rolled hem on your garment.

I hope this helps.

Hi. Take out the looper threads and just leave the needles threaded. And if you want just one line of thread unthread one of the needles.
Of course then your going to have to rethread the loopers later to overlock in which case its important to do them in order.
Upper looper, lower looper, right needle, left. If yours is color coded as most are then the order would be blue, red, green, yellow.
Hope this helped.
Rick