The timing of my sewing machine -- the Singer 7258 -- had gone out of alignment. The most obvious symptom was that the top thread would no longer pick up the bobbin thread. Upon closer inspection, I found the needle was jamming into the plastic of the bobbin housing! Ack! This was also causing my needles to get all bent up.
I am a complete newb to the workings of a sewing machine, so I am fortunate that I had stumbled upon the concept of a sewing machine's timing during prior research. Once I saw that the needle was CLEARLY out of alignment, I jumped straight into searching for how to fix the timing. I came across this video which was enormously helpful and confidence building!
"Score!" I thought. I took a quick gander down at the comments section and saw this scary message:
I took a big gulp at the sight of that omen and then dived into taking apart my sewing machine. And... she was correct - it was not obvious as to how to fix it. I searched around for specifically how to fix the timing of a Singer 7258 sewing machine, and all I uncovered were other people asking the same questions. I was striking out.
It was 9pm and I did not want a several week delay required for sending the machine in for servicing. I have work to do, you know! So, I dove in, poking and prodding at every which thing until I figured out the magical combination. I'm documenting this magical combination so that there will finally be something out there on the web for fixing a Singer 7258 sewing machine's timing!
The first is simple, a normal Philips head screwdriver. The wrench, on the other hand, could be a pain. Its one of those ones you get when you build some furniture -- but a really small one (I don't know the exact size, but the picture has a ruler for scale). I was fortunate that I had two sets of these wrenches that I had collected for computer repair.
Many of these screws have absolutely nothing to do with holding the bottom casing onto the sewing machine. I've highlighted the ones that actually need to be removed, and the rest can be left attached to the case.
When I first got the bottom off, I went straight towards that red herring -- well, ignore it. I have no idea what it does but it didn't do anything with the alignment.
The actual timing gear is behind the plate in the area I circled in the image above.
The Singer 7258 sewing machine has two screws that control the alignment. I could not decipher which one did which, but you do need both.
Turn the hand-wheel on the right of the machine manually (the sewing machine should be unplugged, BTW) until you can see those screws on the timing gear. Once you loosen both of them, then you will discover that turning the hand-wheel will NOT turn the hook / bobbin casing, and you can now rotate the hook / bobbin casing independent of the needle.
You need to rotate the hand-wheel in order to get proper positioning to tighten and loosen the two screws. But, whenever you turn the hand-wheel you also raise and lower the needle even if the screws are loose enough to prevent the hook / bobbin casing from also rotating. So, you need to be careful to loosen, align, then tighten in the correct order so what you expect is what you will get.
I did my alignment by first loosening the bottom screw then rotated the hand-wheel so I could loosen the top screw. I then rotated the hook / bobbin casing to my desired alignment, then tightened the top screw, turned the wheel to the bottom screw and tightened that.
After several hours of trial and error, I discovered that when the top screw is loosened last, which has the needle align just above the feed dogs, then the hook / bobbin casing should be rotated so that the hook and screw are equally distant from the needle.
My machine did not work perfectly after that alignment, but after some rethreading and using the sewing machine a bit, everything started to sew smoothly for the next hour.
Hopefully this guide will help you fix the alignment on your sewing machine!