Originally Posted by
Justsosew
... I try to tell her that there's not as much pulling as she thinks there would be since my theory says that powerful motors actually pull the fabric off center just because of their power.
Motor, hand crank or treadle doesn't have any effect on off-center pulling or guiding the fabric. Either way the machine is run, it's all on the hand wheel not any where else. The feed dogs move exactly the same, the same for needle movement and presser foot tension. If there's any pull it's usually the weight of the fabric itself or feed dogs need adjusting.
The advantage with the hand crank is precision sewing and opmtimal control of needle and feed dog movements. The disadvantage is your right hand is always occupied and we are used to having two hands on the job; that's one of the advantages with treadles and still is. The motor setup makes it faster and it works very well. I lean towards being true to the origin of my machines and not alter them too much. There are plenty of hand cranks turning up in my area, and I would rather just get one of those than remove the motor and light (I like it for most type of jobs). I understand you though, fitting a hand crank requires much less work than rewiring a 1920s motor and sorting out any problems.