ok. the pattern on my fabric is perpendicular to the selvages so I cut 11.25" down the selvage and divided the width of the fabric for the other length so a very generous 18". I didn't get 20 fat eighths as a result.... Only have 18 cut right now but I have found more to get two more fat eighths. It sounds like you can get three fat eighths from the width of the fabric if you measure 18" down the selvage to do that cut. My first oops....
Jaba -- I couldn't read the note you posted but my thinking cap is on... both fabrics are coming for the BOOM 17?