I always use "Triangles on a Roll"' by Quilters Ranch, Inc. The largest size that I have in my sewing room is 3 1/2" and the smallest is 1" and you must remember that this is the finished size. Other sizes are available and reasonably priced. If you use these, sew with the smallest stitch on your machine and it will perforate the paper to make tearing off so much easier. On my Janome I use a 2.2 stitch length.