Positioning the Balance Rail Pins

The next step is to indicate on the key blank the positions of the balance rail pin holes. The balance rail pins will be embedded into the balance rail on the keyframe we will build in the next chapter, and serve as the pivot point for the keys. Draw a horizontal line 6 7/16” [163.5mm] from the front edge of the blank and label it ‘Line PQ'. Draw another line 7 ¼” [184.1mm] from the front edge and label it ‘Line RS’. On line PQ put a vertical line through the center of each natural key that it crosses. On line RS put a vertical line through the center of each sharp key that it crosses. Determine the "center" of these keys by eye and you'll be close enough. These will mark the positions of the natural key balance pins (Line PQ) and the sharp key balance pins (Line RS). Your keyboard blank should look like this.