Mike, my 3-D friends seal their hinge line gaps, but I never have. It's a pretty simple process to do. Some use the same plastic covering (Ultracote/ Monokote) ironed between the beveled sides of their control surfaces. Others use 3M Micropore or Blenderm tape. The Micropore is white vs the Blenderm being clear. You Tube I'm sure has tutorials showing the process...
When I built my Four Star, I covered all of the tail surfaces before gluing onto the fuselage much like an ARF. In this particular case I will be glassing the entire model and painting so I may glass the stab before I glue to wing, not sure yet...
Last edited by VincentJ; 07-04-2019 at 05:20 PM.