i agree with the others. when i build birds' nests it's usually one or more of the following:
- time for a new needle (i have no idea why a dull needle would cause the problem, but ... i don't really understand quantum physics, either, so what do i know? :lol: )
- bobbin in backward
- top threaded incorrectly
- time to clean the shmutz out of the bobbin case. sometimes, it's necessary to take it apart to make sure i've found and cleared all the gunk
- wrong size needle for the thread i'm using
as to having previously spent so much on a problem you didn't have ... unless the repairman gave your machine thorough maintenance service before returning it to you, i'd make sure to never go to that shop again. i paid that much recently to have one of my older machines serviced. i think that's waaaaaay too much, but it runs better now than the day i took it out of the box, brand new. no way i'd get a new machine that does all this one does for $68.50, so i keep trying to convince myself it was a fair price after all. :roll: