1. US20210404279 - Guided wash pipe milling

Methods and apparatus for milling a window for a lateral wellbore in a casing string. An example method introduces a milling assembly into a primary wellbore, the milling assembly comprising: a whipstock, a guide bar coupled to the whipstock, and a wash pipe coupled to the guide bar. The method further includes running the milling assembly to a depth at which it is adjacent to the window in the casing string; securing the whipstock in the casing string; decoupling the wash pipe from the guide bar; guiding the wash pipe to mill the guide bar without milling the whipstock; and milling the window in the casing string with the wash pipe.