Here’s another great project from veteran model builder Rick Michelena. This time, Rick does some fun ARF math: P-51 + P-51 = F-82! He writes: The great element of RC modeling is this: using your imagination allows for any subject to be modeled. Over the past 30 years, I have witnessed the tremendous change that has occurred in our hobby with the introduction of foreign-made ARFs. In fact, when one club member showed up with a Giant Scale Planes .40 sized Mustang ARF, I immediately thought about turning this into something rather unique. Here is my process for turning two .40 ARFs into an IMAA big bird.
I ordered two of these .40 sized Mustangs from Giant Scale Planes. These birds have painted fiberglass fuselages and are available online for only $99.
This photo shows the pre-painted fiberglass fuselages. These will make a great platform for my new multi-engine IMAA legal F-82 twin Mustang.
I have placed the two fuselages on my saw horses. As far as dimensions, the original wing span is 53″. However, the IMAA rules for a monoplane is 80″. Therefore, I
am going to slightly cheat on these dimensions by cutting my own foam wing. As an aside, the stock wings come covered in painted iron-on material. In South Texas, iron-on
finishes tend to wrinkle in the summer heat. Therefore, my collection of giant scale warbirds consists of models I have built, fiberglassed, and painted. Since I will not use these wing panels, I have donated them to another club member.
I have been cutting foam wings for 30 years and have all the equipment to do this. Therefore, I have cut two outboard wing panels for my “stand-off” F-82 twin Mustang. I also have cut a foam center section.
I made 3/32″ balsa wing skins and attached them with “foam safe” contact cement. I then attached 1/2″ balsa strips for the leading edge. I used yellow carpenter’s wood
glue and taped the balsa planks in place until the glue cured. The core on the bottom shows the balsa plank attached to the leading edge. The wing core on top shows the leading edge after shaping.
I ordered a set of Century Jet .60 sized retracts and made gear mounts in the foam core center section which I had built earlier. As you can see, I used wing dowels in the front of the fuselage, and I used a single 1/4-20 metal bolt on the rear of each fuselage. I also made a single center flap that is attached with four Du-Bro giant scale hinges.
This is the top of my center section. When I designed the wing core, I made channels in the wing so that I could route my wires and retract lines. Here is a tip. While this wire looks like FUTABA wiring, it is really 20 gauge security cable. I have a friend who owns the biggest home security business in town, and while watching him work one day, I noticed the wire he was using. It comes as a shielded “four conductor” wire. Therefore, I simply strip the covering, remove the green conductor wire, and insert the other three wires into my drill, twisting them together. As a result, I have all the servo wire I need. I simply solder my servo leads to this wire during final assembly.
I could not use any of the tail feathers included in the kit. Therefore, I simply cut another foam core and made some attachment points. Remember that the fuselages will be fixed eventually at a given distance on the center section. Therefore, the horizontal stabilizer will be held in place by pins and bolts.
Here is how my “stand-off” F-82 twin Mustang now sits on my saw horses. I will be using Thunder Tiger PRO.46 ABCs in this project. Therefore, considering that I will be using 10 X 6 propellers, I chose to make the center section 24″ long. This means the distance between the propeller tips will be 4″. The outboard panels are now 28″, thus providing a total wingspan of 80″ which is the IMAA legal requirement.
As you can see in the frame-up photo, this “stand off” F-82 doesn’t look bad. However, it is now time for filling, sanding, fiber-glassing, primering, painting, and detail riveting. I will save those details for another time and possible future article because I have many secrets to share.
Here is my finished product. I increased the outboard panels to make this project IMAA legal. In fact, the increased wing area makes it easier to fly. I had a great time building this model. Therefore, I am thinking about ordering a Top Flite Giant Scale Mustang in the ARC version. I will order one additional fuselage and build my own center section while using the kit’s left and right wing panels.
Yes, flying RC models is a great hobby. However, I also enjoy owning airplanes that are quite uncommon at the field. By developing building skills, your next dream RC project is only limited by the effort you are willing to put forth.
I thought IMAA was disbanded years ago. Can’t find anything about them on the web now. Why is “IMAA legal” of any concern?
Great project, nicely executed! Indeed, you can be creative with ARF’s!
Nice job of ARF-bashing, looks great!
One question, for attaching the balsa sheet to the foam cores, what brand of contact cement was used? I have an old giant scale kit that calls for Southern’s Sorghum and that’s not been available for several years.
Thanks for any advice!
Hot Springs, Arkansas
Comments are closed.