Can a rivet be too long?
As much as possible, choose a rivet with a shank length equal to the thickness of the material you need to clamp with an allowance of 1.5 times the rivet shank's diameter.
Some rivet suppliers indicate the grip range of their rivets which approximates the range of thickness that a rivet can handle. Find rivets with a grip range that closely matches the total thickness of the material you need to clamp. Read more