Thursday, August 30, 2012

Paper Stomp Saturn V, completed


I finished up the cardstock Saturn V from AlaskaPaperModelWorks.  The finished model is 2.875" in diameter and 28.8" tall, including the nozzle bells. This is only a semi-scale but this equates to approximately 1:138 scale.

First, I'll backtrack and identify the parts that are provided and also identify what I changed [changes in brackets]:
  • Lower body - Three wraps, four half-cone fairings, four fins and four nozzle bells.
  • Upper body - 2nd-3rd stage transition, 3rd stage fuselage, 3rd stage-to-CSM transition. [I added an inner layer to the 2nd-3rd stage transition, a cardboard bulkhead to the top of the fuselage, and a piece of twine mounted in that bulkhead.]
  • Nose section - Collar support (attached to the topmost transition), replaceable CSM tube (slips over the collar, 5 sets provided), capsule cone (5 sets provided).
  • Pressure tube - Two wraps, top former laminate (aka bulkhead, 2 provided), bottom former laminate (aka centering ring, two provided), tube plug (two provided), upper plug wrap strips (three provided); [I made my own 2-part tube due to the larger barrel that I'm using. I also cut the formers and plug from thicker cardstock rather than laminating the 110# stock. I didn't use support strips but rather notched the top of the pressure tube and glued them to the top of the plug. A section of twine is attached through the former bulkhead.]

 My main deviations from the kit were the upgraded pressure tube and configuring it for mid-body drag separation.  The printed 2nd-3rd stage transition is attached to the upper body but not to the lower.  Instead, I cut a 2nd transition and attached it to the lower body. So the top and bottom sections slip over one another.  I am hoping that this attachment will hold up under boost and will separate near apogee.  I attached twine to the former bulkhead on the top of the pressure tube and another piece to the bulkhead on the top of the CSM tube.  Hopefully the attached photos will clarify this design. What's not clear is whether it has any chance of working.  I only know one way to know for sure!

As far as construction goes, the kit was easy to build and I didn't have to build any trim details. That is what I wanted for a stomp rocket with possibly a short life expectancy. YMMV. Once again, I used too much glue (Aileen's tacky glue) and made many inexact cuts. The bigger the model, the less forgiving it is to small deviations in the cuts. My fairings didn't mate with the body perfectly and the tubes aren't perfectly round. All these are builder's issues, not the kit's. 

Unfortunately, I won't be able to report on how the stock kit flies.  Even if it works well, I've just made too many changes to give an accurate report. The glue has to dry overnight and, if the weather cooperates, it could fly over the long weekend. I bet the park will be too crowded and I'll have to wait until after Labor Day.