While repairing, make triangles invisible and unclickable to allow working on the insides of a part
Hiding triangles has the benefits of allowing unobstructed view at, and access to, the inside of a part. Hidden triangles are fully invisible from both sides, they only draw during special conditions such as applying transparency during using the clip planes, and they do not intercept clicks or focus even when they would otherwise cover other triangles further inside.
To hide triangles,
The keyboard shortcut for hiding selected triangles is I.
To show hidden triangles,
The keyboard shortcut for un-hiding triangles is V.
Hide triangles to examine internal surfaces of parts