Abstract: A bale twine knotter comprised of a rotatably mounted billhook for forming a loop of twine thereabout and a wiper arm with an improved adjustably mounted wiper for sliding a twine loop from the billhook while the twine end is retained in a jaw of the billhook to complete the formation of a twine knot. The adjustable mounting of the wiper permits the spacing of the wiper from the billhook to be adjusted easily and accurately and permits the wiper and wiper arm to be made of strong, rigid materials.