General Repair Procedures (cont).
(a) Determine thread size, grip range, style, and material of rivnut to be used.
Grip length equals combined thickness of materials being fastened
together. Grip range of rivnuts must encompass grip length.
Drilling creates metal chips which may
injury. Eye protection is required.
enter eyes and cause serious
Do not drill deeper than necessary to install rivet as you may drill
through other side of panel.
Drill hole size must match size of rivnut being installed. Quantities of
sheets may be drilled at the same time when held together with sheet
Drill hole in structure.
Remove all metal chips and remove burrs from drilled holes.
If a countersunk head rivnut is being installed,. countersink hole using a
100-degree machine countersink.
Thread stem of appropriate pullup stud into rivnut. Stud should protrude
through open end rivnuts, or be 1 1/2 threads from bottoming in closed end
Coat rivnut body with sealer (Item 28, Appendix D) before installing.
Insert rivnut in hole. Make sure sheets are held tightly together before
With pullup stud parallel to axis of rivnut, pull up on rivnut. Exert firm
pressure but do not bend or buckle metal sheets.
Make sure fastened parts are not loose, rivnut does not rotate and rivnut
head is seated tightly against surface. Make sure rivnut threads are in good
condition. If threads are damaged or rivnut is improperly installed, remove
it and install a new one.
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