The majority of the spar cap rivets were set using a Numatx HTX-C3K rivet squeezer. This NuMatx unit is a hydro pneumatic devise that is very powerful for it's size. However, to squeeze the 5/32 rivets, you need to run it right up at the maximum allowed pressure. The flange height on the Nexus spar is deep, too deep for standard yoke openings. As a result, I modified my spar yoke by welding in a section to add height, and I also opened up the upper leg of the "C" channel above the die. Still, you need to be careful which die combinations are used for each spar cap stack height to avoid bottoming the yoke on the spar flange while squeezing. In the end, the squeezer did an excellent job setting the rivets. Any rivets that could not be reached by the squeezer were set using an Avery C frame tool.
