The 4.5 rivets are the perfect length as one can see by looking at the rivet gauge.
To accommodate using solid rivets on the hinge, the assembly order was changed slightly. The bottom skin was not riveted to the internal ribs until after the hinge was riveted to the lower skin/spar assembly using a longeron yoke on the pneumatic squeezer.
Using the pneumatic squeezer to rivet the hinge to the anti-servo tab’s skin and spar.
The solid rivets look great! To bad they won’t be seen.
Once the hinges were riveted to both the left and right anti-servo tabs, the lower skin of each anti-servo tab was then riveted to the ribs using the flush rivets I’ve been using on all the external skins in place of the LP4-3 dome rivets.
Riveting the lower anti-servo tab skin to the ribs with flush rivets using the pneumatic rivet puller.
Once both left and right anti-servo tab skins were riveted to the ribs, the upper skin to spar joint was riveted with LP4-3 rivets finalizing the rivets on the anti-servo tabs.
To prevent the skin from lifting away from the spar at the outer edge of the spar during riveting,
a Cleco clamp is used to hold the skin tight to the spar when setting the first rivet.
Using the pneumatic rivet puller to pop the last row of rivets that will finalize the anti-servo tabs.Two more finished RV-12 tail feathers!