Sonotube - Unsanded with Epoxy Sealed Edges - Front End
  Sonotube-Unsanded Epoxy Sealed Edges-Front End
 
This is a close-up of the front end of the tube illustrating the area where the two-part epoxy was applied to exposed edges of the tube and spider vane support holes. In addition to moisture proofing, the epoxy also provided noticeable rigidity to these formidable areas.