tryitall, you don't put the tack in your machine. You need for your machine to be in a cabinet (or at least that's the way I do it). And, no, the tack doesn't go IN the cabinet either. I used masking tape or painter's tape and taped the tack straight out to the left of the needle - with the point facing UP. Then you put the middle of a piece of fabric on the tack, the edge of the fabric under the foot, and start sewing. The fabric spins in a circle as you sew. I put a rubber eraser over the tack to keep the fabric from slipping off.
Hope this is makes it more clear.
Tate