I bought this machine from the 1960s (cost: ~5 Big Macs). I did not clean it or oil it as I wanted to just see if it works.
It made a straight line without issue. Then for the 2nd straight line I spun the wheel manually (no motor) to see things work in slow motion. The top thread got bundled below the plate. I cleared that & started over. Then went to the narrowest zig-zag setting and the needle broke. I think I used the motor for the zig-zag.
I’m just starting to learn. I know from videos that pushing the fabric while the needle is down can bend the needle and put it in harms way. I don’t think I was pushing or pulling the fabric when the needle broke. So I wonder what would cause this-- does this mean the timing is off and needs adjustment?
I’m not enthusiastic about doing much experimentation at this point because needles seem pricey enough that I don’t want to break many (1¼ the cost of a Big Mac in my area buys 5 needles). But I just removed the top thread and bobbin and installed the empty bobbin case. When I manually spin the wheel with no thread at various zig-zig widths, there is no apparent contact with the needle. So perhaps the thread occasionally bundling up under the plate is part of the issue.
update: if I load thread and manually crank for the zig-zag patterns, most stitches are missed. The thread is plunged in from the top but does not get grabbed from the bottom most of the time.
Could be an issue with bobbin tension to tight? https://www.sewkitkit.com/sewing-machine-tension-issues/