10Cargomaster.lt1.doc
[headline: George Maiorana’s C-133A Cargomaster]
[subhead: Find out more about the construction of this award-winning model]
[Author: George Maiorana]
[Photos by the author, Jennifer Orebaugh, and Jay Smith
[Sidebars in text file: Specifications and Jay’s introductory piece]
[Callouts: There are two videos so make space]
~~~~~~~~~~~~~~~~~~~~~~~~
C-133 specifications
Prototype Model
Wingspan: 179 feet, 8 inches 130.6 inches (10.88 feet)
Length: 157 feet, 6inches 113.4 inches (9.45 feet)
Height: 48 feet, 9inches 35.1 inches (2.92 feet)
Propeller: 18 feet 13.09 inches
Wing area: 1,481 square inches (10.28 square feet)
Scale Ratio: 1:16.5
Radio: Futaba 14MZ
Motors: MaxCim NEO 13Y x 4
Batteries: (4) 5,000 mAh 5S LiPo
Propellers: 13 x 10CF three-blade made by builder
Builder George Maiorana
~~~~~~~~~~~~~~~~~~~~~~~~~
George Maiorana is a well-respected craftsman whose aircraft have won several awards over the years. His newest creation, a C-133A Cargomaster, is equally impressive. The 10-foot, 8-inch wingspan model took 51/2 years to construct.
The inspiration came after a trip to the National Museum of the US Air Force in Dayton, Ohio, when George found the full-scale C-133A parked outside of the hangar. This provided complete access to the aircraft allowing him to take numerous photographs that he later used to construct the model.
George’s aircraft made its debut at the 2014 Toledo R/C Expo in Toledo, Ohio, where it was selected Best of Show. It then traveled to Delaware to take part in the 60th anniversary celebration of the C-133, held at the Air Mobility Command Museum at the Dover Air Force Base in Delaware on May 9-10.
The C-133 Cargomaster was developed by the Douglas Aircraft Company as a four-engine transport and was first flown on April 23, 1956. It was the largest turboprop transport ever to be accepted by the U.S. Air Force. Thirty-four C-133A aircraft were delivered and variations of the aircraft would remain in service until 1971.
George’s C-133A made its first flight at the International Aeromodeling Center in Muncie, Indiana on July 10, 2014, with Dave Pinegar at the controls. Other than a last-minute change from three-blade propellers to two-blade propellers, the maiden flight was uneventful. It was clear that George and Dave are comfortable working together and competing in Team Scale at the Nats.
Just three days after the maiden flight, George and Dave won Team Scale and they were also awarded the NASA Flight Achievement Award. This award is decided upon by a vote of the contest flight judges, in which the subject best duplicates prototypical flight, taking into consideration uniqueness of a subject and its flight characteristics.
To learn more about George’s C-133A, be sure to check out our exclusive interview with George at Toledo and our maiden flight video at www.ModelAviation.com.[dingbat]
—Jay Smith
[email protected]
~~~~~~~~~~~~~~~~~~~~~~~~
[Headline: A Method of Making Flush Head Rivets in Aluminum Covering]
If we could turn back the clock eight years, we would find me in my workshop working on my first 1/15-scale B-29 project. As with all of my projects, I like to define the most troublesome and difficult parts of the build and solve them before committing to that particular phase of the undertaking.
I had been researching B-29 prototypes and found that most B-29 airframes had a natural aluminum finish and the time had come to select a prototype for the model. The first B-29 I had decided to model was that of a restoration of Miss America ’62 located at Travis Air Force Base in California. This aircraft had painted wings and a horizontal stabilizer, but the fuselage and vertical fin were aluminum.
I began experimenting with adhesive-backed aluminum for covering the fuselage. I was convinced that I could cover the model with aluminum and have it look scale, but I could not find any tooling to do all the flush rivets—believe me, a B-29 has a lot of flush rivets! To use the natural aluminum finish I had to find a fast, easy way to apply one-million-plus rivets before committing to covering the aircraft in an aluminum finish.
In my “butterfly” fashion of modeling, work on the project came to a halt. Off I flitted to another part of the workshop to find a way to do flush rivets. After roughly 30 hours of making scrap out of everything from toothpicks, combs, tubing, hacksaw blades, syringes, and anything else that lay around the shop, I came up with the following method of applying 1/15-scale flush rivets to adhesive-backed aluminum finishes.
Although I had discovered a method, it still took some time to make the tooling and apply the rivets. The tooling is basically a strip of .005 hard aluminum (lithographic plate) with a large number of holes of equal diameter pushed into it.
Figure 1 shows the five main requirements for making the tooling: a hard work surface (glass); a soft spacer material (cardstock); a rivet tool material (lithographic plate); a hole-alignment device (rule with holes); and a hole-producing tool (hardened steel awl).
The tool making begins by taping a strip of cardstock approximately .015-inch thick to a glass surface. Next, tape a piece of lithographic plate down, followed by a tool to space the holes over it. I lucked out and found a marking rule that has holes in 1/16-inch increments (Figure 2).
Make a short awl from .030 piano wire, being careful not to anneal the steel when you grind the point (Figure 3).
Sitting in a comfortable position with awl in hand, begin pushing the awl straight down to the glass in each hole. When you have finished a 12-inch strip of holes (in roughly 15 minutes), you can remove the tape from everything and see the results of your tedious work (Figure 4).
Turn the lithographic plate with the holes over and your results should appear as in Figure 5. Gently draw a piece of 400-grit sandpaper over the previously pierced holes. A couple of gentle passes with the sandpaper and you should have a nice neat row of male flush rivets in the lithographic plate (Figure 6).
Finalize the rivet tool by trimming the lithographic plate to roughly 1/8 inch either side of the holes by scouring the lithographic plate several times with a hobby knife (Figure 7). A row of masking tape on the either side of the rivet holes, as shown in Figure 7, will help prevent the edges of the tool from leaving lines on either side of the row of rivets as you apply them.
To apply a row of rivets, prepare the surface by marking off where you intend to apply the rivet lines with a felt-tipped marker. Figure 8 shows a wing panel with the places for rivet lines marked.
Begin by taping down the tool at one end, pull slightly on the other end while aligning the tool to the marks, and run a craft stick down the holes from one end to the other (Figure 9). Use firm pressure on the stick and only make one pass on the holes. Keep the stick on the holes so you don’t get any lines from the tool next to the rivet line.
Figure 10 shows a wing panel with all the rivet lines applied. Figure 11 shows two tools that I made to do 95% of the riveting on the model. The bottom tool is used wherever there is a butt seam on the aircraft. Butt seams have two rows of offset rivets on either side of the seam for strength. This tool takes longer to make, but a 12-inch pass applies approximately 760 rivets.
Different parts of the aircraft required making different tools in special patterns to achieve a neat appearance. The two main tools will hold up to complete the entire riveting job.
Well, there you have it. This rivet-tool system works well for my aircraft’s scale appearance, and I think that you could adapt this method to suit your particular aircraft by changing the size and spacing of the holes.[dingbat]
—George Maiorana
[email protected]
