If you didn't read my last blog, these are "penny whistles" made to the design of Guido Gonzato.
The black pipe makes a perfectly serviceable instrument, but it is much harder to see the pencil marks, and, conversely it shows the scuff-marks from sandpaper much more clearly! A strip of masking tape along the tube was useful to mark out the positions for the holes.
Here's a picture of the two whistles together.
73 Hugh M0WYE