One of the tricky things about the RV-3 being so small is that the top skin curvature is pretty tight. This makes it tricky when it comes to mounting an antenna like the one for the Garmin GNS 430W ? it has a fairly large (several inches across) flat bottom, and doesn?t match the curve at all. If you try to mount it flat, the four screws will deform the fuselage ? not good!
The solution I came up with was pretty simple ? I just built a shim (more like a ?shoe") out of micro and resin. I started by drilling the appropriate holes in the fuselage for the mounting screws and Coax connector. Next, we taped the fuselage with vinyl tape, and covered the bottom of the antenna the same way. Wax or mold release completed the preps, then we mixed up a squirt of resin and a bunch of micro (nice and dry), buttered the bottom of the antenna, and squished it in place using the screws to hold it in position. After it cured, I pulled it all off, removed the tape, cleaned up the fuselage, and remounted the antenna with the shim in place. A razor blade was all I needed to trim the ?flashing? off flush.
Paul
The solution I came up with was pretty simple ? I just built a shim (more like a ?shoe") out of micro and resin. I started by drilling the appropriate holes in the fuselage for the mounting screws and Coax connector. Next, we taped the fuselage with vinyl tape, and covered the bottom of the antenna the same way. Wax or mold release completed the preps, then we mixed up a squirt of resin and a bunch of micro (nice and dry), buttered the bottom of the antenna, and squished it in place using the screws to hold it in position. After it cured, I pulled it all off, removed the tape, cleaned up the fuselage, and remounted the antenna with the shim in place. A razor blade was all I needed to trim the ?flashing? off flush.
Paul