If you have made a bunch of HST's with 5" squares you should now have a bunch of 4" finished size HST's--maybe 4 1/8" if you were really careful pressing, sewing and cutting. The little HST's are one third the size of the bigger ones which is going to be a very, very small little block. Unless you really like to work with tiny blocks I would also suggest that you use your 5" squares for the smaller HST's and use 13" squares for the larger HST's which will then finish at 12"--actually 12 1/8" but I always trim mine down as MTS also mentioned.