I designed and built this to mount a VIRB onto one of the struts of my Piper PA-22 Tripacer. It should work with any other aircraft strut that has the same profile. Two mounting block designs are provided, one for a GoPro mount and another for the Ram ball mount system.
The main components are printed. The assembly also requires some 5/16 threaded rod, 5/16 nylock nuts, 5/16 washers, 1 1/4" neoprene washers, m8 x 25mm machine screw, m8 nylock nut and 3/4" wide x 5/16 thick automotive weather stripping. For the VIRB a GoPro to VIRB mount adaptor (which comes with the VIRB) or Ram Mounts VIRB adaptor and single socket arm is required.
Since the attachment point isn't very big I was concerned that if I printed it as part of the mounting block, it might fail at that point. So what I did was design it so that the GoPro adapter would fit into the block, allowing me to use more material at the mount point. This required a more accurate print job than my printer was capable of. That meant some cleanup by hand. The GoPro mount/adaptor is secured with the m8 machine screw.
The mounting block is for the Ram Mounts single socket arm part RAP-B-200-1. Clearances are tight and the part or the arm may need to be massaged slightly.
The assembly is held together with 5/16 threaded rod and nylock nuts. All 5/16" hole need to be cleaned up with a drill. Weather stripping that is squeezed to 5mm is used for a snug fit and to absorb vibration between the strut and the inside of the caps.
The mounting block(s) are designed with a cavity so that a nylock nut can be used to tighten the rod to the cap. The second outer nut adjusts the tension on the block and the amount of friction provided by neoprene washers between the block and the cap.