One of our fellow Carbon Cub EX builders came up with this angled shim that allows the builder to use a hand or air operated rivet puller to pull the rivets that attach the ribs to the front and rear spars. Without an offset puller the rivets will not seat properly against the ribs. It is a good idea to use something like this shim to pull the rivets. The following diagram shows the basic dimensions that could be used, the only real important dimensions are the 12 degree angle and the hole placement. The hole placement will allow you to get into the necessary tight spots. Make sure that you deburr the edges so the ribs don’t get scratched. You could use about any material to make this shim. The rivet shaft will be pulled at a slight angle, but the rivet face will be seated flat against the rib.
Rivet Puller Shim.jpg
Thanks Tony