The 15-91 is not a treadle. i have a Singer 15 from early 1900's and one made in the 1940s they have different numbers so it is confusing. They were made even earlier but harder to find. The ones with potted motors are much easier to find though. You could treadle one with a potted motor or a Japanese clone but you would have to find a spoked hand wheel that fits and you would lose the belt guard and bobbin winder. Do a bit of research first. First remove the motor and wiring, old hand wheel, and belt guard. Then put on a spoked hand wheel. Put on the clutch knob parts on and you should be good to go. Next put it on a treadle belt etc - it will work with out a bobbin winder if you use a sidewinder. I'm thinking the hand wheels are not all the same depth so you will need to find some thing that interchanges. The belt guard replacements do not come with screws. If you are using a clone you should be able to come up with a belt guard and reuse the screws or maybe the original belt guard will fit over the hand wheel. The potted motor 15s do not come with belt guard screws those are attached different. The holes are there though - go figure... Maybe someone will start making screws for that since there are none made these days.
Last edited by miriam; 01-11-2016 at 03:52 AM.