I have the 1473, which is the next machine up from yours. Could you post a picture of your foot--it should be just like mine. And yes, if you still have your IDT foot down, the darning foot won't fit. Mine came with a darning foot, I didn't have to buy it separately. Also, when you are ready to sew with this foot for FMQ, don't put your pressure foot lever all the way down. There is a little shelf like spot in the place where you lower it and you move it just enough for it to fit on that. That gives your foot room to move over the fabric as it hops, but also gives you tension on your top thread.