Angular Conical Fairing Formulas/Equations for Soviet Style Rockets or Estes Expedition

[RocketTheBruce]

Does anyone know the math formulas/equations for the angular conical fairings on Soviet style rockets, or the Estes Expedition? I have the equations for a body tube transitions, so I'm thinking the angular conical fairings are a special case of transitions. Thanks in advance, RocketTheBruce

 

[tsmith1315]

The Expedition fairings appear to be cylindrical and cut at an angle, not conical.

 

[bjphoenix]

You can look at the conical transitions in the photo in the first post of my thread here. These transitions go from a point where they meet the center tube to a part of a circle where they meet the outside pods. Essentially they are pieces of a pointed cone with the point off center.
https://www.rocketryforum.com/threads/panelizing-scale-models.175715/
I did some measurements in autocad and some other calculations then essentially plotted points on a piece of paper to cut out a test pattern. Then based on how that piece fit I did a couple of trial and error rounds to refine it. I had a top view of the rocket in autocad to work from. I could map out a uniform number of points around the circumference of the lower tube then measure from the point on the center tube where the point occurs out to each of the points around the circumference. I also know the height of the transition. This gave me 2 sides of a right triangle so I calculate the hypotenuse which is the length I use to map out the pattern. This is hard to describe in words, if someone really wants to do this I could provide some diagrams.

 

[mjennings]

Tim van Miligan's Model Rocket Design and Construction 3rd edition has a procedure. It's somewhat similar to what @bjphoenix describes above iirc.

 

[GlenP]

Estes Expedition uses a body tube with a partial ellipse pattern wrap as a cutting guide.