I have a 3-thread Bernina serger (about 25 years old) that I adore. I replaced it once with a 4-thread Bernina, but chose to have the 3-thread tuned up and put back into service. When I did that, they lost my needle threader. If you know anything about your serger, you know you need that needle threader! I ordered another one that is a bit different hoping I'd never have to use it. I'm a firm believer in threading your serger by tying the new thread onto the remainder of the old thread and snaking it through. So, a week or so ago, a thread broke. AAAAAA. It was the looper thread that is hardest to get to and gives old sergers a bad name.
I had to thread it from scratch. I probably have done that twice in the last 25ish years! I tried to open the cloth guard and couldn't do it. I tried to thread the derned thing without opening the cover and couldn't do it. I went to consult the manual. I couldn't find it. It's been in my bookshelf for who knows how long, but it's not there now. Oh no. That would be too simple. I went online and ordered a photocopy of the manual. It came today and well, there it was, a clip that needed to be pulled back to open the cloth guard. Eureka!
It took 15 minutes more, but I got it done. I was almost ready to face the ridicule at the Bernina shop by taking it in to be threaded. But now, I sincerely rock. My serger is back in action - I faced the looper and won. Take that Bernina machine thingie!