Sorry to be so late in jumping in here. I just looked at your picture of the machine. When the bobbin is one the side like that, so is the hook. The hook passes on the scarf side of the needle opposite of the long groove. So you have to thread side to side not front to back. Usually it means orient the long groove to the left and thread it left to right.
Years ago I had a German machine that looked a lot like yours. I don't remember the name, but it took 16X231 needles. The 16X231 is AKA DBX1, a very common industrial needle.
Cathy
Originally Posted by
frudemoo
It picks up the bobbin thread and looks like it's going to make stitches and then it sort of draws the bobbin thread up through the eye of the needle or something. You can go for a good inch or more before noticing there are no stitches and before this thing starts to happen with the thread looping up. The thread doesn't break and it doesn't get tangled in the bobbin case. It's nothing I've ever seen before and therefore I'm stumped!
The other manual I have says to use a system 1738 needle with the long groove facing to the front.
I just happened to have some Schmetz needles that have this number on the packet, but they are round shank. There was a giant (denim weight) flat shank needle in it when I got it but we suspected that this needle wasn't right, however changing the needles hasn't seemed to help the problem, nor has it made the problem worse.
Any clues?