With 1.5" logs and 2.5" 'hearth' center square, you will end up with an 8" block when your quilt is sewn together.
For a quilt that will fit a queen sized bed, make 110 of these blocks; set them 10 blocks across by 11 blocks down and add borders about 4" wide.
With 2" logs and 2" hearth, you will end with a 10.5" block when your quilt is sewn together.
For a queen-sized quilt make 72 blocks; set them 8 blocks across and 9 blocks down to measure approx. 84" x 94.5"; then add narrow borders if you wish.
Jan in VA