In a bowl, combine the flour, sugar, poppy seeds, cream of tartar, baking soda and salt.
Cut the butter into the flour mixture with a pastry cutter or your fingers until it resembles cornmeal.
In another small bowl, beat the egg with the orange juice; add the liquid mixture into the flour mixture and stir until just blended (you want to try and avoiding overbeating or overhandling the dough).
Gently shape dough into a ball and cut in half.
On a flour surface, pat each half into a circle, about 1/2 inch thick and about 8 inches in circumference.
Cut each circle into 6 even wedges, and place the wedges, about 2 inches apart, onto the baking sheet.