Star Scraper

mid-power super-roc sport flyer

By Brian Mardirosian

Introduction:
Always wanted a Mean Machine when I was a kid, but never got around to getting one. When I raided the house recycling bin after the holidays, I discovered five identical wrapping paper tubes. Being on the flimsy side, figured it would be a test to reinforce them enough to fly on a G motor in the form of a super roc.

Nose Cone:
Shaped out of a styrofoam ball used for a Christmas decoration that had seen better days. Hmm, have to say the same thing about the nose cone.

Recovery System:
A parachute that I had created for a min diameter bird that was way too big for it. Small for Star Scraper (about 20" I'd say) but the long, light body tubes would be gliding on the way down, figured it was enough.

Body Tubes:
I first wrapped the tubes with a layer of craft paper and thinned wood glue. Once that set-up, I then applied one layer of copy paper and thinned wood glue. When everything dried, I was amazed with the amount of strength added to the tubes. They went from being easily bent with slight pressure to being much stronger than Estes tubing. I was also pleased with the fact that the tubes remained fairly lightweight, certainly lighter than some heavy-duty tubes of similar size used in rockets. Overall, a worthy compromise in strength-to-weight ratio, and you can't beat the price.

Motor Mount Tube:
Nothing all that exciting to report on, basic two centering rings of 1/8 balsa with a slightly oversized motor mount tube of thick cardboard tubing from what I believe was the core of a fax machine paper roll.

Fins:
Again, nothing all that exciting to report. I moved the fins 3" away from the bottom since the super roc design in inherently over stable, and I wanted to give them some protection from fast landings.

Couplers
I heard it time and time again from others more wise than I that couplers makes or breaks (literally) a super roc. 13" coupler for the mid-body separation point, with 6" couplers used in the three other joints. Since I used a tube of the same diameter as the rest, I needed to somehow reduce the circumference of it. Instead of doing it the right way, I just overlapped the material and filled in the rest with a scrap piece and sanded a bit. It worked, and I didn't have to risk the chance of ruining a coupler.

Launch Lugs:
I tried my old 1/4" screw eye-in-balsa method. One of them promptly ripped out when the rocket was on the pad. A larger set of lugs were needed. I ended up using 1/2" peg-board loops. With a little work, I was able to sink the connective material flush with the surface of the balsa blocks on the rocket, with the peg board hooks resting on the surface of the rocket itself. A little 5 minute epoxy in the appropriate places, and I had me an impressive set of launch lugs. They worked great!

Painting:
Grabbed what I had on the shelf and went to work, just one layer of each. If I were to do it over again, I wouldn't have used black. Didn't think such a small area would be affected so much by the sun, but it is.

First Flight:
After the launch lug issue at the first, I was able to finally get this bird into the air. Taking advantage of a calm spell, Star Scraper rose without incident up a G38-4. Unfortunately, at about 2 seconds after burn-out ejection occurred. No damage to report, but I'd say the rocket was only 400' off the ground, tough to say since it is so tall. All of the kids were pointing and commenting on it, and some of the adults had some snide comments about it, tehehe. It certainly is a looker, and it towered above the Mean Machine that was also flying that day.

Conclusion:
It took a long time to finish from beginning to end, but it was worth it. Certainly an attention-getter (134"x2.1"), and it proves that paper and wood glue can significantly add strength with little weight to body tubes.

Star Scraper had a date with some swamp creatures. Launched on a G35-4 and the flight looked great, but no recovery system deployment. Was at the RSO table at the next launch, minus about 8 feet and a bit soggy, tehe... Recovery system was intact, as well as the fins and launch lugs and I have a feeling if I stuck a nose cone on what I had left after it dried out, it would fly fine.