Sport Rocketry

SPORT ROCKETRY MAY/JUNE 2017 11 the transition sections. I used many 3/16" foam board bulk- heads throughout the rocket to give it side strength. I calculated each tube section and cut the height to al- low the seams between tubes to be covered up later by the airframe stringers. Making the stringers was easy, as I used styrene sheets from Plastruct. These are plastic 7" x 11" Cor- rugated Siding sheets. I used 1:32 scale for the lower sections of the Saturn V and different scales for the upper sections where the stringers are more closely spaced. The lower sections of the Saturn not only had foam board bulkheads in them, but each bulkhead had four 38mm holes and one 54mm center hole cut through them. The motor tubes ran through the holes and were glued to each bulk- head, which gave added strength overall. There were also two 1" x 2" wood boards inserted that ran inside the entire length between the main parachute chamber bulkhead and the bot- tom motor bulkhead. Large washers were used with long wood screws to secure the bulkheads at each end. These two major bulkheads were individually made from seven layers of foam board glued together—still lightweight but strong. You can see pictures of the foam boards with a design on them. I created the bulkhead pattern (see Figure 10) and printed it on label stock and placed them on the foam board material to make cutting out the bulkheads easier and accurate. The fins were made from basswood and fiberglassed. The fin fairings were made from the same heavy card stock, with five layers laminated using the padding glue. The shape of (Left) Figure 4. Dimensions and markings for the 1:25-scale Saturn V. Figure 5. Additional internal structure details of the Saturn V. Figure 7. Parachute chamber of the 1:48 Saturn V.

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