How to mend Singer Concerto 2

the thread is bunching on underside of fabric it looks like birdnest?

Singer zigzag 457 Stylist not threading bobbin/making stitch?

Singer 507?

My CG 500/550 Singer Sewing Machine's bobbin isn't working?

pedal machine Singer serie K10736204?

singer foot pedal ?

machine motor running the wrong way?

1965 Singer 275k sewing machine foot pedal?

How can I replace the Top Vertical Shaft Bevel Gear for SINGER MODEL 248?

Engine revving up ?

My bobbin case for Singer 2662 will not seat right and I cannot sew?

What size needles can I use for my Singer 39a3?

foot pedal 619490-001 CR505?

Replacing a gear in Singer Stylist 457?

where can I get a thread guide post for a Singer Touchtronic?

I'm in Australia and need a Bobbin case for a singer 196K205?

Hello zigzag industrial singer 457 u105 not stylist is missing stitches?

how to get the tension right on my machine?

Why won't my Singer Touch Tronic pick up the bobbin thread? ?

Singer 201 went bang , smelt and now won’t work?

Singer model 750 Golden touch and sew?

Singer 522?

Need a service manual for a Singer Treadle Sewing Machine Model 66-1?

obtain?

Machine Stuck in Reverse?

Bobbin won't wind?

singer HD110?

Presser foot is loose?

Singer 6234 Tension problems?

Why does a sewing machine motor overheat?