Why would the cotton be broken thus unthreading itself from the needle eye? It's the Elna 1000,

Probably not all to do with tension as to the thread. Is it the same in the bobbin and top? Is the thread new (and not cheap thread) is the needle the correct size for the material? and often times the needle is threaded incorrectly, a very common mistake. We all do it. :-)

Have you got a tangle under your fabric? If so, release the fabric and rethread your machine, making sure the foot is up during threading. Otherwise check the feed dog under the foot. There's usually a switch somewhere that brings the feed dog up or down. If it's down the fabric won't feed. Another point, what type of fabric are you sewing. If it's leather or leatherette you'll need to use a roller foot. Hope this helps.

make sure to keep long thread tail for the top & bobbin
of 4 to 6 inches & pulled behind the needle

Are you threading the bobbin in correctly? the right size thread and needle for the fabric?

Love the TX, its a gem. Is it the top thread that is breaking before the needle?

You could check the following:
tension dial - set to 5 and working okay? Unthread, turn it to zero and floss between the discs with a clean piece of cotton waste to remove any lint and dye build up. Turn back to 5.

Thread - are you using a good quality polyester or cotton wrapped polyester thead on top? Same thread top and bottom. Also check the spool doesn't have a little knick in it to hold the thread tail, sometimes the thread will catch in this as it runs off. Turn the spool up the other way. Using a felt disc under the thread spools also aids in a clean flowing thread. You can always make your own by just cutting a circle of felt about an inch diameter and punching a hole in the middle with your awl. Have you got the little thread eyelet out from the top accessory box and have the thread running through this?

Now check needle isn't bent blunt or has a burr on it and look around the needle bar or the eyelet above it to see if there is any sharp protrusion that is rubbing or catching the thread. Put in a new needle, flat shank to the back, and rethread down to just before the needle. Lower the pressure foot to engage the tension device and pull the top thread, there should be resistance but if it feels like its just not releasing at all, then the tension device could be faulting.

Remember, to always hold the two thread tails firmly behind the sewing area at the start of every seam to avoid them being pulled into the bobbin area.

Test sew again after trying the above; if no joy then take it to an Elna dealer. In face if the machine has not had a service clean in past two years then I'd definitely recommend you look up your nearest Elna dealer and take it in for one. Well worth the money for this little gem of a machine.

Are you using bargain priced threads? They tend to have small "burrs" in them and stick at the needle's eye and snap. Have a close look at the ends of the broken thread for small knots

Do you mean the auto needle threader?

Mine won't work on very small needle sizes so I resort to the old manual needle threader for these. Ditto for twin needles.

Otherwise its a case of pulling the auto threader down so the hook swings into the needle eye, then pulling the thread over the face of the needle and catching it into the hook, then release the threader so it pulls back through the needle eye, taking the thread with it.

The only other thing that springs to mind is "is the needle at the top position in its stich cycle so that the threader lines up with the needle eye?

hope these ideas help a little.

You need to get the gear from your elna dealer. To time the machine, you want the tip of the hook to pass just over the top of the eye of the needle when the needle is in the left most or right most position depending on which side the eye of the needle will be higher

you should try adjusting the needle hight, the tensioners, the bobbin rension, belt tensions.

Thread the needle last.Thread the lower looper first.
sewman7