I'm currently applying the final clearcoats on what started here as a Brodak Zero. I thought I'd show some info on all of the build modifications I did to it. None of this would have been required, I just wanted to try and update some things and also end up with a more scale overall look when the model was finished.
The only original Brodak kit parts left in this model are the wing ribs and the fuselage stock. We are all "spoiled" these days with laser cut kits, but that's a good thing. This was a pre laser cut kit, so early on an evening was spent just sanding and shaping the wing ribs to have them all line up better. Even with that I still ended up shimming the L/E airfoil outline in a few places for the ribs to reach the L/E sheeting. I swapped from balsa to spruce spars, and added main spar and T/E shear webbing tip to tip. I didn't care for the kit wingtip shape or design, so they were scrapped and I built new ones to my own preference. With the new tips it now spans 51" where the kit was 48". I also built new flaps with 1/2" more chord along the entire span, giving some more wing area and control. Hiding inside is a Brodak 4" bellcrank on a new platform. Pushrods from Control Line Central will be carbon fiber with titanium ends and Du-Bro 4-40 ball links. The last detail on the wing after covering with Polyspan was adding a 6" wide carbon veil around the entire center section. In the end I'm really happy with the wing.
On the fuselage I decided I wanted to do it as built-up profile, instead of the solid design per the kit. I also felt the profile outline was too long and skinny, just didn't look "right" to me. First, I added a 1/2" wide by 1/4" tall "stringer" to the top and bottom of the fuselage to make the outline taller. On the top, I ran it from the rear of the canopy to the tail. On the bottom, I ran it from about the L/E of the wing cutout to the tail. Doing this also helped stiffen the fuse. I should also mention that I extended the fuse stock a bit before doing this. With that I added 1" to the tail moment. I also added material to the top and bottom of the nose so that I could cut a new outline later. After all of that, I cut out the center to make way for new internal truss work using 1/2" wide by 1/8" stock. Next was making new longer motor mounts, 1/8" five-ply nose doublers, and a 1/2" thick tripler. I tapered the fuse from the wing T/E to the tail before sheeting it with 1/8" balsa. That sheeting butts up to the plywood nose doublers for a 3/4" wide overall fuse. Once I got the fuse built and sanded to my liking, I added carbon veil to it as well. Last with the fuse was making a height adjustable fuel tank mount.
The tail surfaces are all new with a bit larger area to them. The overall stab span is 2" longer than stock. All of the surfaces were built up with 1/8" balsa. After tapering the elevators and rudder framework, everything was sheeted with 1/16" balsa. After that all of the surfaces were cut out to a more accurate scale outline. I also scratchbuilt and added flap and elevator "fairings" to go where the control surfaces blend to the fuse. To me, this was a detail that really helps add a more scale look.
I also bent up new 5/32" landing gear and made new L/G doors. The tailweel wire is new too.
The entire model is covered with medium silkspan except for the Polyspan portion of the wing. The carbon veil is over the silkspan and Polyspan. The finish will be all Brodak dope and there is more info about that in the Painting and Finishing section here on the forum. When I get it all done and reassembled, I'll have a finished report in the Open Forum...