Prior to dimpling all the ribs an inspection was made to make sure the outer skin would sit flat on the ribs. There were a few places where the fluting caused small bulges where the skin would lay so the ribs were all checked and tweaked as necessary with a small pair of flat nose pliers.
The dimpling was done with the pneumatic squeezer with the small custom made female die on the inside of the flange as to not mar the metal at the bend where the rib flange transitions to become the rib’s web. Also of note, with the exception of the far outboard ribs, all of the ribs have lightening holes that are raised from the web … this interferes with the yoke on the squeezer preventing it from being square to the flange at various locations on each type of rib. All the holes that had good access were dimpled with the pneumatic squeezer the remainder were dimpled with the custom dimple dies that are to be used with a hand pop riveting tool.
dimple dies with the hole in them for a nail to be inserted into the pop rivet tool.
