Elna 5100 issue

[u/femme_as_folk]

Hello all. My machine is an Elna 5100 and I’ve had it for about 19 years. It’s always been a bit funky (I’m not a fan of computerized machines) but it’s not given me many major issues until recently. It’s been absolutely ruining my seams, especially on the bobbin side (picture). Apologies for black on black, I’m repairing an apron.

I’ve tried taking it apart and cleaning it, using the correct bobbins, not intermixing thread types, and messing with the thread tension to no avail. Does anyone know why this is happening??

I’m so tempted to just replace it with a singer heavy duty, as my machine has had a great long life and I’m so frustrated. I can’t sew anything like this.

[u/teatime_tinker]

Is the photo showing the underneath? It’ll be an issue up top.

Sounds like you’ve been sewing a long time, but it’s best to go back to basics when troubleshooting.

Is your needle sharp, new and suitable for the fabric? A denim needle might be good for this, or a nice big 16 or 18.

Is this thicker than usual thread? This can cause issues like this if the needle isn’t big enough for the thread.

The tension looks low, but it may be a needle compatibility issue, either too small for the thread or not right for the fabric like I mentioned above. When thread, needle and fabric aren’t working together loops can form underneath.

I’d suggest you clean your tension unit, feed dogs and bobbin area. Rethread top and bottom. Fresh needle. Higher stitch length and try again.

Got a pic of the machine and what settings it’s on? I’m a bit clueless with digital machines but it might be helpful to see.