The profile of the stabilizer of my Potez 58 is bi-convex, while the bottom of the fin is flat. The fin will be glued on the stabilizer and it is necessary to add a base under the fin, which will follow the shape of the stabilizer.
So I made a fin seat using the usual technique of epoxy heavily filled with micro-balloons that I described in the previous article.
The first step was to wrap all the areas of the stabilizer, fin and fuselage that should not be in contact with the resin with cling film.
Then I prepared an epoxy resin that I loaded very strongly with micro-balloons to give a thick consistency
The resin is applied to the stabilizer in a thick layer and I put the fin on top of it and held it in position with pins. The thick resin will take the shape of the stabilizer and fill the gaps between the fin and the stabilizer. We let it dry for 12 to 24 hours.
After drying, the pins are removed and the fin is released. The plastic film has prevented a bonding to the stabilizer. The masks and film are removed and the fin is left with the excess resin to be removed.
This excess is cut with a cut-off wheel using a dremel at the limit of the fin. We finish by sanding with water on the edges.
Here is the finished fin and its seat. Once installed on the stabilizer, it perfectly fits the profile of the fin.
It remains to put some primer and to paint this part before gluing it in position on the stabilizer