Openrocket question. Nested tubes/boattails?

Calling on all of you OR gurus out there! I am playing around with an idea that would nest a boattail within a boattal to create a nozzle of sorts. While I am curious about the sim, my primary purpose here is to establish dimensions and aid in figuring out fins, so using a body tube as a place holder would be of some help, an actual boattail is my best case objective.

I know that I can use an inner tube and set it to the larger diameter of the transition and get my dimensions that way. If I remember, I'll post my OR file this evening if it will help in visualizing what I'm trying to do. If it is of any help, I am playing with Dynamic Gas Stabilization principles to bury the engine a bit.

To do a nested boat tail, you'll need to use one of the developer's versions of OR. More specifically, the pods function.



and after I did that, I remembered that the Mars Snooper also has nested boat tails.

View attachment BBoatttail CConcept.ork

Thanks for the info. I downloaded the developers version a while back but haven't messed with it for a year or so. Now that I found the thread that included instructions on how to access it, I can give it a go again!

BTW,
Glad you forgot about the Mars Snooper, I find that variation on the Velociraptor way cooler!