Chicken Hawk, 3ch RC biplane

I decided to modify the build process of the bottom wing. The process is similar to the top wing but in this case I will keep the bottom sheet firmly held flat while gluing on the top sheet. Second, I am going to glue the top sheet in sections: LE, TE, then wing root. I'll be fitting each section into place individually instead of gluing it as one assembled piece. To do this, I cut the TE sheet with a 1/4" extra material at the edge where the TE meets the LE. Once the LE is glued and dry, dry-fit the TE, mark the line where both edges meet, and cut. The edge may need some (very) light sanding with a straight sanding block to get a good fit The two bottom sheets, spar, ribs, and dihedral brace are done. The left wing panel is held down to the building board and has the LE sheet fit and glued. The TE sheet is waiting for its turn. TE sheet now glued. The balsa sheet might need to be damp in order to help in forming it to the rib curvature. The left wing panel is done and perfect

I started with building the top wing then the bottom wing, and included some picture and comments as I progressed with this first step. I followed the exact same process when building the bottom wing. For each wing I traced and cut the set of four LE and four TE sheeting according templates. I made the templates out of packaging cardboard. The top-wing templates are visible in top right of this picture. The bottom sheeting (3 pieces) of each wing panel include the LE, TE, and wing root sheet that I glued together to form a single piece.  Closeup of magnets holding 1/16" balsa sheeting. Spar and ribs. Left wing with-top sheeting attached with clothes pins. The top sheeting was glued in three stages: TE then LE, and finally wing tip. I used water to dampen the the top sheet, mainly LE and wing tip, to help form and curve the sheet to the ribs. The plans call for the top sheeting to have the same dimensions as the bottom sheeting. I found that if I extended the overall width by 1/8&q

A friend at our RC club started using a magnetic building board instead of the traditional pinning method. He shared his insight and I decided to try this out when building the Chicken Hawk. After researching the topic I found several web pages and instruction videos on the topic, and here is what I ended up using for the build: 12"x24" galvanized sheet metal that I purchased at the local hardware store for $12 24x square magnets with metal plates. This type is used for cabinet doors and are sold in bulk on places like Amazon for a 24x (73c a magnet) or 100x count (46c a magnet) All for about $30 I attached the sheet metal to the lower half of my 24"x24" building board and started my build. This picture is of the bottom part of the left wing, sheeting, spar, and ribs held firmly down while glue is drying. I would recommend getting the magnets with the metal plates on them. The plates are removable and seem to align the magnetic field when a stronger hold is needed.

A few months ago I was browsing Outerzone  in search of my next scratch build project. I was not sure what I was looking for when I came across several biplane designs and that's when I made up my mind: my next build will be a Bipe. I narrowed my search for a specific wing span range and R/C capabilities, and the Chicken Hawk caught my eye.  I bookmarked the plans for a later date and continued my flight lessons with the club. A couple of months later I came across an AMA magazine article by  Bob Benjamin describing his build of the plane from a kit available at Retro RC LLC. Now I had two choices: build from scratch or get the kit. Five months later I'm building the Chicken Hawk from scratch. Bob Benjamin's article and the info from Retro RC was an added bonus to Ted Strader's detailed build article that is also posted on Outerzone. Combining all the tips and tricks from these sources will sure help get over some of the difficult parts of the assembly. I printed the