I have been having a problem back riveting AN4 rivets, they are almost always about a thousandth or so proud of the dimple when set. Never any issues with the AN3 rivets. I have double checked the #30 dimples, and they are fine and the rivets are flush before setting, I have tried more "mass" by adding a tungsten bucking bar on top of the back rivet plate but this is tricky to not get it to fall off and dent the skin but does help some. I even tried the back riveting plate (from Avery) on a concrete floor and still got a rivet that was slightly proud of the dimple. I tried lowering the pressure to about 40psi and held it on longer but I am worried I will work harden the rivet by hitting it too long. So far this is more cosmetic than anything but I really would like to figure this out. Open to suggestions... thanks
Avery back rivet plate
Cleaveland back riveting set
3X rivet gun
Avery back rivet plate
Cleaveland back riveting set
3X rivet gun