I am attempting to hem a pair of jeans and when I sew the top thread isn't catching properly and is making big loops between when it DOES catch. I have tried adjusting tension, stitch length, almost everything the manual has suggested... HELP!!

Adjust the tensioner setting until it runs smoothly

If the top thread sews a few inches and then breaks, something is catching the top thread and holding it until it breaks. Usually, this will happen when using the old style thread cones with the slit in the edge to keep the thread from raveling off the spool. To prevent the thread from hanging up, turn the thread spool over so the slit is at the top instead of the bottom. Sometimes top thread breaks will happen if the thread becomes looped around the thread spool pin.

Remove the thread, ALWAYS RAISE the presser foot and then rethread the upper thread. Verify that the thread path is correct and that the thread has not looped around a guide.

If the thread is fraying at the needle eye, the needle/thread are not compatible. Also, the tension may be too high.

Check that the upper tension disk is clean--no gunk buildup or thread pieces stuck.

If the thread is actually breaking when it penetrates the needle plate hole, there may be a burr or nick somewhere below that is catching the upper thread. You can wrap your finger with a piece of fine fabric, like an old pair of hosier, fine knit fabric, etc. and running your finger around in the bobbin area, under the needle plate. If you get snags, then you have a burr or nick. If it is small, you can sometimes smooth it with a fine emery board. If it is a large burr, you may need to purchase a replacement part.


Why Does My Top Thread Keep Breaking Sewing Machine

Sewing Machine Problem 1 Thread Breakage

Sewing Machine Thread Keeps Breaking

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You need a couple of things. One is to flatten the seams before you try to sew them. One of the best is to spread the hems on a wooden cutting board or simiilar smooth surface and beat the hems flat with a flat faced hammer. This is an official sewing hammer: http://www.fashion-incubator.com/archive/tools_and_supplies/ and it will compress the fabric so it doesn't lift your presser foot up and let the tension off the top thread (which is what's causing your looping problem).

For crossing thick seams, you need a shim to keep the presser foot flat while sewing. These are usually called hump jumpers or jean-a-majigs, and are a couple of bucks. Or you can use a fold of fabric in the same way: http://www.youtube.com/watch?v=WbYenXIDaDk http://www.youtube.com/watch?v=ZKdW_vIZLBo

Alternatively, you can do the jeans hem alteration that pros will charge you more for (because it's "fashionable"), and it's also faster and easier. Often called Euro-hemming: http://www.sewmuchado.com/2011/06/tutorial-how-to-hem-jeans-and-keep-the-original-hem.html

It loops, it's just that your shuttle isn't catching the loop. The loop is formed on the upstroke of the needle on the back or "scarfed" side of the needle. If the shuttle point doesn't catch that loop, no stitch.

First make sure you have a fresh needle. If still no stitch... take it in for service. (clean, lube and time)

Make sure your needle is fully inserted into the needle bar and isn't bent or blunted.

You have described your problem just fine. Have you just changed the needle in your machine? If so, check it is in the right way, you want the flat shank to the back.

The needle has a scarf (scoop out) at the back - if it is facing to the front then the rotary hook (bit that goes around the bobbin and catches the top thread) can't catch the needle thread behind the needle.

Also check needle is fully up into the housing, this could also cause problem.

I'd suggest that you visit www.sewingabout.com and check out the pages on general sewing machine use, care and threading up, lots of helpful pictures and information which may be of assistance to you.

If it isn't your needle backwards (very easy to get wrong, happens all the time), then the timing could be out, which isn't so easy, but as its new I'd be very suprised if this was the fault. Just check needle, make sure top and bottom threads are threaded correctly and have another go. Also, remember to turn flywheel towards you.

Could be one or a combination of the following factors:
old dry brittle thread
burr, or broken thread loop or damaged metal somewhere in the threading path that is catching the thread.
Top thread spool is catching, sometimes the thread will catch on the paper label on top of the spool or in the little knick on the spool, or if you have left a long loose loop of thread at the back and then its catching on the spool holder or some part of the machine and impeding the thread flow.
Bent, burred or blunt needle.
Needle in backwards
Incorrect threading up on top thread, maybe looped twice around take up lever?
Dirt or lint in the tension discs

I suggest you locate the manual and clean the machine, particularly the tension discs. Then oil and thread up from scratch with fresh needle, wind a new bobbin and check the thread path is correct.

If you still can't get a good stitch, then take it in for a service, tension device may be faulting.

Did you engage the feed dogs for sewing?

Get in touch with the store!

Sometimes when I need to use heavy thread for top stitching to reinforce a seam that has come undone, I will use the heavy thread on the top and regular thread on the bottom. I haven't tried it the other way around for hemming but I would think it would work. I do not currently have a Bernina.