Tuesday, September 22, 2015

Trial ringtail

I've continued fretting about the potential Coleoptere/Coccinellida/Flying Stovepipe build. The good news is that the stability issue isn't as bleak as I had thought. A big point is the BIG ringtail needs to be light. For aesthetics, I changed the nose cone to the Big Bertha type and shortened the body so only about 5" is exposed. Only 3oz of nose weight seems to be required to get one caliber with an F44. The performance really sucks according to RockSim, but it should be stable on a D12 off a 4' rod.

Some thoughts I've kicked around:
  • Build a paper ring. Maybe. Need a stiff mandrel and some suitable thick paper (gummed packing tape or whatever). Building a ring would give me more control over the size. Would there be a significant weight savings?
  • Build a ring from 1/64" ply. Still need a mandrel and I'm sure I'd ruin my plywood. Would reduce the weight by a couple of ounces (actually weighed the material).
  • Build a ring from fiberglass. Messy and by the time it was stiff enough it would probably be too heavy. I've only built  a few 29mm and smaller tubes.
  • Build a balsa ring with rib and spar techniques (now I'm just sounding crazy).
  • Use the paper mache round box but lighten it up. 
Now we get to the real point of this post. I had the paper mache ring and didn't want to use it as is so I drilled a bunch of holes in it. I got over an ounce and a quarter off so it's under 3oz. I then found some scraps of Monokote and applied it. See the photo. I did a bad job since I apparently have forgotten I everything I ever learned about that process. Plus, it wouldn't surprise me if the old Monokote wasn't in great condition. It has too many wrinkles and the tabs folded over to the inside aren't adhering well. The holes covered well after I shot it with a heat gun (may need to hit it again). So, I'm going to continue thinking but may throw in the towel and use this one anyway.

    20150922_144453

    PS - A Mini Bertha and a part of a Quaker Oats bin would also work well.