A twine arm assembly (22) is provided with a guide member (38) controlling the movement of a twine arm (32) during a tying cycle. In order to facilitate the insertion of new twine (26) into the twine arm (32), said guide member (38) is made of two parts (70), (72), which can be locked on each other or which can move with respect to each other in order to bring the twine arm (32) into a position, in which twine (26) can be inserted easily.
