Originally Posted by
miriam
I'm thinking the gear on the 401 is a tad shorter - the 500 or 600 motor will work in the 401 but the bobbins won't wind in the 500 if you put the 401 in it.
Correcto Mundo. The 500 motor has a taller shaft with a spiral wound thing at the top to run the bobbin winder.
I think the drive gear on the 401 might be slightly larger in diameter but without having them side by side I can't be sure.
Joe