under-tighten russian

• недокру́чивать

  to under-tighten, to not twist enough, to not turn enough

• недокрути́ть

  to under-tighten, to not turn enough, to not screw in completely

Examples

• Обруч, стягивавшийся на бочке, скрипел от давления.

  The hoop tightening around the barrel creaked under the pressure.