TOMARK, s.r.o.
Airplane Maintenance Manual
Chapter 20 Standard Practices-Airframe
Page 88
Issue: 11.AUG 2016
Removal
NOTE
Observe the following when removing rivets:
▶
Use a drill bit by 0.6 mm (0.025 in) diameter smaller than the rivet
shank and rill up to the depth of 2/3 of the total depth riveted parts.
▶
Remove the drilled heads with a sharp cuter.
▶
Drive out the shank with the soft material mandrel diameter by 0.1
mm (0.004 in) smaller than rivet shank diameter.
▶
The rivets, which cannot be driven out should be drilled out full
depth.
▶
When removing rivets, be careful that chips and rivets do not fall
down to areas were sensitive mechanisms are located, e.g. guides,
control bearings etc.
▶
Remove rivets from the side of the rivet, which is more accessible.
▶
Drill out the rivet head and drive out the shank.
Riveting Procedure
NOTE
Observe the following when riveting:
▶
When drilling, fix by clamps or clecos mutual position of assembled
parts.
▶
Holes of higher diameters pre-drill with a drill bit of smaller diameter
and then re-drill them to the final size.
▶
Fit the parts being connected and drill them together. Hole diameter
must be by 0.1 mm (0.004 in) bigger than rivet shank diameter.
▶
Disassemble the parts and deburr the holes.
NOTE
Observe the following for sunken rivets:
▶
Perform conical countersinking of the rivet head by 5° smaller apex
angle (e.g. the head with angle of 100° will have countersinking of
95°±1°).
After countersinking, the cylindrical part of hole with min. length of
0.3 mm (0.012 in) must remain in material.
▶
Countersinking must be performed in such a way that the rivets head
overruns the area before riveting max. by 0.2 mm (0.008 in), the rivet
head must not be under the surface level (sunk).
▶
Before applying the bonding sealant (applies to fuel tank only)
carefully clean the connected parts of impurities and degrease contact
surfaces by appropriate agent, e.g. industrial spirit.