Scratch building an RC airplane is a lot of fun and very rewarding. This DC-3 Project has been a great learning experience for me. I have scratch built a couple of aircraft from Mark Rittinger plans and they are great looking, strong, light-weight and my best flying aircraft. Building on that experience (no pun intended), using many of the same building techniques from the previous builds, most of the construction has been straight forward and predictable. There are some new things I have learned with this project including:
- Main spar system joining outer wing panels
- Retractable Landing Gear
- Twin engines & dual batteries
- Custom Drawings made by me using 3-Views
3 – View drawings offer three different views (top, front & side) giving the modeler accurate overall measurements for depth, width & height (all necessary to create a model in 3 dimensions). These views (like the ones shown above) are usually basic line art drawings and not photographs. I used Adobe Illustrator to import the 3-Views and created new layers to trace the outlines of the views. From there, I can overlay the views allowing me to know the width, height and length of all of the parts I need to cut to make the skeleton of the aircraft. Things like the spars, formers and other parts of the model are drawn out on the drawings for use later as templates during construction. The end result will be a model that looks pretty scale.
Finding good quality & accurate scale 3-Views can be almost as much of a challenging as building. Fortunately, I managed to find some great ones from a very unusual source. Using Google image search for “DC-3 3-Views”, I came across the image that look like full size plans. When I first saw these I was shocked to learn these are plans for a wooden model made back in the 1940’s. During that time, model building was very popular and Maricraft (the manufacturer) wanted to set the bar for high quality scale model kits. In an advertisement for this kit, they state that stacks of blueprints, handbooks, field manuals and photographs supplied by none other than Douglas engineers, major airlines and even the United States military were used to produce these “super-detailed” plans. The 1940’s kit came with an engineering sheet showing all of the details of this model kit. This image is that engineering sheet.
Once I learned of these drawings, I went over to RCGroups.com and started searching for someone who may have these tucked away. RCGroups is a great resource for the RC enthusiast. I got lucky and found a member who had a high-res copy of the engineering drawings from the model kit. They were scans of the original Maircraft model company DC-3 Kit X-2 that was produced back in the 40’s. After working with Adobe Illustrator and outlining all of the important sections of the aircraft I ended up with a set of drawings I could size to any scale. In my case the model is a 1/14th scale version of the DC-3.
The last image here is part of my drawings that has each locations for the formers. You might notice that there is an outline around the outer area of the fuselage. That is the center spar and the fuselage is made up of two halves. (right and left). This spar or “Keel” as it is known strengthens the structure along with the formers that are glued to it. Foam is sandwiched between the formers and sanded to the shape of the formers. See the fuselage post to see some pictures. I realize that these are not plans and you will notice that there are no measurements. The more experience I get the better my drawings will be for future projects. For now, it is good enough.
More to come!