How to mend Singer Gears Machine

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

Singer zigzag 457 Stylist not threading bobbin/making stitch?

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

Bobbin won't wind?

Engine revving up ?

Singer model 750 Golden touch and sew?

machine motor running the wrong way?

Singer 188K1 presser bar stuck?

1965 Singer 275k sewing machine foot pedal?

Machine Stuck in Reverse?

obtain?

singer HD110?

how to get the tension right on my machine?

Why does a sewing machine motor overheat?

Singer 6234 Tension problems?

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

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

singer foot pedal ?

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

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

Replacing a gear in Singer Stylist 457?

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

Singer 507?

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

pedal machine Singer serie K10736204?

foot pedal 619490-001 CR505?

Presser foot is loose?

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

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

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