Sewing Machine: loose stitch that's easy to pull out.

Here's a manual for your machine:

ELNA eXcellence 730 Instruction Manual

If your machine does not have a "basting" stitch selection, you make your own basting stitch by:

* Setting the stitch length to the maximum
* Loosen the upper tension so the bobbin thread lies flat under the fabric

Then to gather or remove the basting stitch, it is easy to pull on the bobbin thread.

If you haven't already, install a brand new needle. Be sure to use good quality thread--no old stuff or bargain bin variety.

Remove all the thread from the machine.

Raise the needle until it is at the highest point it will reach before it begins to lower.

RAISE the presser foot and rethread from the beginning--verify the thread path is correct. Pull at least 5 inches of thread tail through the needle.

Check that the bobbin is installed correctly.

Set the upper tension to somewhere around the midway point between high & low number.

Pull the bobbin thread to the top of the fabric:
How and Why to Bring up the Bobbin Thread

When you begin to stitch, gently hold both thread tails with your left hand and begin stitching slowly to start.

Why does my thread keep pulling out of needle

Tilly and the Buttons Five Common Sewing Machine Mistakes How to Fix Them

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Be sure to use a brand new sharp needle that is compatible with the thread and fabric (see link below). The type of needle may need a larger scarf/groove to shield the thread (ie, top stitch or embroidery) and pierce the fabric easier.

If your machine has the option for a straight-stitch (vs zig-zag) needle plate, you may want to try using that. The small needle hole will restrict the fabric from being pushed down into the bobbin area.

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&ved=0ahUKEwi1sYKT-oTOAhUo34MKHQXFCxcQFggkMAE&url=http%3A%2F%2Fwww.schmetzneedles.com%2Flearning%2Fpdf%2Fschmetz-needle-chart.pdf&usg=AFQjCNHTR52AmqwzvyCjbXmD5Ch52Va5_Q

All About Needles

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The only thing to really tighten on a bobbin case is the tension screw. (Unless, what is really loose is the mechanism--hook, shuttle--that the bobbin case fits into.) It will probably be worthwhile to just bite the bullet and buy a new bobbin case for the machine. They aren't that expensive and it certainly will relieve a lot of potential future frustration.

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it's possible that the machine is out of time
you can check with youtube or fixsewingmachines.com for video's on the problem

If your thread tension is OK and u have correctly threaded machine, I would check manual for first the right bobbin and put in machine right. I have have issues from badly wound bobbins too. If you have replaced correct needle and your fabric, thread and tension are good, I would check manual for the right bobbin tension. Wish I knew more to help......

Check to make sure that the thread running between the tension disks. A quick check is to lower the presser foot and then pull on the top thread. If you do not feel any tension, then it may not be ran in between the disks. Also, check to see if your bobbin is inserted correctly going counter-clockwise. This can cause the "loose" loops and thread jams in the bobbin casing.

Yes, it does. There are a couple of reasons the bobbin thread could be bunching up on the underside of the fabric. It could simply be that the machine needs cleaning. Take the bobbin assembly out, brush all the old lint out as best you can, reoil the machine once it's all clean, and make sure there aren't any little bits of thread caught in the bobbin assembly. Rethread the machine (carefully) and change the needle. This solves the problem usually--especially if the machine was sewing along fine and the problem develops suddenly. '
The other thing to check is your tension. It could be that the top tension is too loose. But different color thread in the top and in the bobbin, stitch a few inches (be sure to held the top and bobbin thread ends behind your needle as you start to stitch) and check. WIth the pressure foot down, adjust the tension, and stitch again. Keep stitching, checking, and adjusting until you see little if any bobbin thread on the top or top thread on the bobbin.
Another thing to reminder: use the appropriate thread and needle for the fabric you're sewing.
Let me know if this works, ok?

Robbie

Elna bobbins have holes on the top, so wind the bobbin with the holes on the top too. The Lotus bobbin winder doesn't have a tension device, thread just goes through an eyelet. So, place your scissors curved handle on top of your thread spool as it unwinds the thread to ensure the thread then winds onto your bobbin evenly. Also watch the bobbin fill and give the thread a nudge with your finger tip to fill top and bottom as well as the middle part, you want it to wind evenly across the full width of the bobbin. When full, pop bobbin winder back to left, cut thread and pull off the bobbin.

Then place the bobbin into the bobbin holder with the holes on top, and pull the loose thread tail around anti clockwise into the tension device and gently "click" it into the tension spring with the tip of your finger while holding the bobbin still with your other index finger.

You will be able to tell if it is in tension if you then pull the thread and it doesn't come out of the tension spring. It should feel firm with resistance but still release thread to a gentle pull. Now thread the top down to the needle and holding the end of the needle thread, hand wind the fly wheel towards you to lower the needle and pull up the bobbin thread. Close the bobbin cover.

Always hold the two thread tails at the back of the sewing area as you start stitching a seam until you have stitched at least 4 or 5 stitches to avoid thread jams.

Lotus is a lovely vintage machine - there is a user group on Yahoo Elna heirlooms where you can find lots of info and pictures shared by members.

I have an Elna 2005 machine and had a similar but opposite problem whereby the tension up top was too tight - thread wouldn't pull smoothly. I found adjusting the feed dog lever slightly helped the stitches a lot, even though the needle tension up top is no better. Hope that helps! :-s