Tonight, I realized that the pop-rivet pull techinque for dimpling wasn't giving an adequate dimple in the tight spots of the elevator ribs. The dimple itself just wasn't deep enough to receive the rivet head completely, leaving it slightly proud in the hole (sticking up). Therefore, I placed another order with Cleavland tools for a few more items to make my life easier. I ordered another deburring bit that fits in an electric drill (this makes hole deburring remarkably faster). I also ordered a tight spot dimpling tool from them. This tool consists of a steel bar with a female dimple die in it that mounts to the workbench, either with screws or, as I did it, using C-clamps. Then you use the matching male dimple die, a rivet gun and a back-riveting attachement to "hammer" the male die into the female die, leaving a perfect dimple in holes with little or no clearance.
