I made this dimple bucking bar. The instructions showed it and said I would need it to dimple the end holes on the flanges of the aileron rib. And I did. The trailing edge of the rib gets narrow and you can’t get any other dimple tool in to dimple because the flanges are on both sides of the rib web making for a tight fit. This is ¼ inch steel bar stock with a 3/32 hole drilled through and then counter sunk using the #40 counter sink. You put a rivet in to check depth until it is just right. This ¼ inch dimple bucking bar fits behind the hole, than you put a rivet in the hole and hit it with the rivet gun using the flush rivet set. The rivet itself acts as the male dimpling tool and dimples the hole down into the steel dimple bucking bar. Hang on though the light weight bar transfers a lot of rivet shock into your hand. Later I used this to rescue a rivet I had to drill out. I messed up the dimpled skin and spar removing a cracked rivet. So I put this dimple bar behind the hole, put in a flush rivet and hit it with the gun. This fixed up the two holes so they were re-dimpled and ready to be re-riveted. Worked great. Can't tell I had a screw up. These other photos show more riveting. I think my technique is improving. Yea?
