Version 2:
After flying my foam structure 7" diameter Jupiter C for a season, I decided to convert it to a Redstone missile cofiguration. This was one of my first foam models and had a 3" parachute bay that made it impossible for me to fit my hand down into the bay to fit the ejection charges. It was a serious pain to try to fit the wires/charges in place and fit the chute into the long narrow tube using a stick and a flashlight. I also had made a removable altimeter pod that I can swap from model to model that I wanted to fit. It also fits better with my personal nuclear triad, I'll have a pershing 1A, Redstone, and Titan II all at the same basic size/scale in both standard and lightweight versions, plus my foam Atlas Missile as my backup nuclear deterrent...I also wanted to make sure it was balance to fly on I-200 motors as well.
So, I figured out that I could cut the top of the structure and 3" tube off right at the forward ply plate and fit a 4" by 14" parachute bay at that point, add some stringers to extend the fuselage, and then do a small 4" by 7" ejecting cone section and convert it pretty easily. I'll do it in one of the white test schemes since it is already painted that way on the lower half. Sims to about 1250' on an I-200 down to 400' on a G-80. AUW should be right around 4 pounds with the larger motor, and very close to far 101 with the G-80.
The way I did the structure it was easy to peel off the sheeting at a joint, add the extra stringers/centering ring and go from there.
I contacted Gord at Roachwerks to make me a 4" by 7" foam cone with a dowel up the middle to take any tip abuse on landing. It doesn't need to be fiberglassed since the cone will only weigh 6 ounces or so.
I'm making the forward fins out of 1/32" lexan which will be covered in white monokote trim and I've made the little steering nozzle/covers that go around the forward fins out of 2mm and 6mm foam. I've removed the upper half, removedthe portion of the lower sheeting to remove the old altimeter bay, added the stringers back in and adding the new 4" centering rings and recovery attachment. Next up, add the 14"x4" parachute bay when it arrives, add the upper straight stringers and the angled portion of the nose that will stay attached to the model, and then re-skin it. I guess it's recycling....
Left to right, original Jupiter C, and Internal structure, Modified structure with extended centering rings/stringers and the planned internal structure