Shroud-finned rockets?

[BlueNinja]

Does anyone have plans for a scratch cone-finned rocket? I was wanting to build one for 29mm motors. How is the shroud constructed?

 

[wwattles]

A guy in my club just goes to the store, buys an oil funnel, cuts the point off, and hangs it onto the bottom of a BT!

You could also use the template widget and make a transition for whatever your BT's OD is to however large you want your shroud to be. Print it on card stock, add a joint strip for overlapping, and then coat the inside with some thin epoxy to harden it, slide it into place and let it dry. (Hanging it upside down will let the epoxy run up into the shroud/bt joint and make it solid.)

WW

 

[BlueNinja]

Is there any thing to support it besides the epoxy? Would the reinforced cardstock be enough for a G motor?

 

[teflonrocketry1]

Look at Essence Model Rocket Reviews (EMRR) do a seach for funnel.

https://www.rocketreviews.com/cgi-bin/search/searchall.cgi?funnel#RA

If you have RockSim be sure to look at the Rogue Aerospace Deep Surface Probe; A.K.A. Bruce Levison's RockSim Challenge. I have the kit and can supply more details if you want.

Bruce S. Levison, NAR #69055

 

[shockwaveriderz]

blue:

You might need some internal bracing inside the funnel: take a look at this for ideas:

https://www.dars.org/jimz/kc-13.htm