New Way Firecat 4 Build, Part 10, Engine Mount and Fin Grain Fill

The engine mount is glued in with 1/8" of the engine mount tube extending out the back.
The engine hook ends up being centered in a corner of the main air frame tube between the fin locations.

The tube seams were sanded with 200 grit followed by 400 grit. This tube had an overlap seam so no CWF was needed.

A fin was set to see how long the root edge was. I wanted to mask the gluing area so the primer/filler couldn't soak in and seal the tube from the glue.

Here's the main tube after spraying with the primer/filler and sanding.
The tube took two coats to fill the seams and smooth out the surface. These New Way tubes are rougher than a typical Estes style tube. In the end they can look good but there will probably be some  highs and lows in the surface.

The balsa fins only needed one pass with the Carpenter's Wood Filler.
TIP: After you sand the surface always go back and look at the fins under a bright light. You might find some areas that will need some more sanding.