This writeup covers the Singer 128-13 machine, serial number JB55772. This is the hacklab machine, there are many like it but this one is ours.
The manual for the machine is in the box labeled "Sewing Machine Attachments". If it isn't, then someone has lost it and should be found and ostracized. There is a PDF of the manual available from Singer's site. Singer has gone to some lengths to make their site an undeeplinkable heap of crap, so I saved a copy of the file. It would be good to move this into hacklab.to storage space, since I may forget why I have that file and delete it eventually.
The main way that the lab machine differs from its manual is that instead of a foot pedal to control the motor speed, it has a knee pedal. The "pedal" is a 7-shaped piece of metal that fits into the metal-lined hole in the right side of the front of the base. It hangs below the tabletop the machine is sitting on. Pushing the pedal to the right makes the machine run faster, releasing it makes the machine stop.
This image may help to make things clearer.
The needle should be positioned so that the hole runs left-to-right, not front-to-back. The thread passes through from the left to the right (towards the body of the machine).
The machine has trouble feeding and pushing the needle through two thicknesses of rubberized canvas. This is probably because the material is very high-friction.