Drilling, Dimpling, Squeezing, and Fitting

Paul has been learning some sheet metal skills over the past few days. Measuring and cutting sometimes prove more difficult in practice than in theory. He mentioned this morning that he would be especially focused on "measuring twice and cutting once" in completing this task. That's pretty good advice when measurements in aviation are often made down to hundredths or thousandths of an inch. While the fabrication of this cover plate may not be quite that precise, the finished piece still needs to match the existing mount, be structurally sound, aerodynamically clean, and pleasing to the eye.

When I caught up with Paul this afternoon he'd successfully measured and cut his raw material and had moved on to connecting the two pieces of sheet metal together. In this instance he needed to drill, dimple, squeeze, and fit.

Paul drills the two holes necessary to secure the two pieces of aluminum into one structural piece.

Paul "dimples" the pieces. This pre-forms the metal to accept a flush rivet and increases the structural integrity of the union of the two pieces.

Paul then "squeezes" one rivet into each of the holes swelling the rivet to tightly secure the two pieces of aluminum together.

Paul then tests the fit to see what other adjustments may need to be made before finishing, priming, and painting the cover plate.

Stay tuned.