ARCAS scratch build help

I need advice in building my 1st scratch built rocket. My goal when I became a BAR was to build upscale versions of my childhood fleet. My very 1st rocket back in 1968 was the Estes ARCAS. As a BAR I built the Semroc 18mm motor version, but my fin plates left much to be desired. I thought about getting the SLS, but the complex fin/plate/boat tail gave me pause. I was waiting for a kit with a prefabricated fin can to simplify the build. Well with 3D printers, someone has created fin cans to fit several body tube sizes. I am going to use the fin can for ST-20 body tube: (https://www.shapeways.com/product/F...24-mm-motors?optionId=83655024&li=marketplace).

My dilemma is what nose cone to use. The 18mm Semroc kit uses a Secant Conical nose cone (BNC-58AC) & the SLS kit uses a Secant Ogive (BNC-70HAC). The closest NC I found to fit on the ST-20 is the BC-2082, Ogive.

All these NCs were found on eRockets. I searched the net but could not find any Secant Conical/Secant Ogive NCs to fit on the ST-20. ST-2

#1 Does anyone know where to purchase a Secant Conical/Secant Ogive nose cone to fit the ST-20?

#2 If no to the above question, should I have one custom made or should I just go with the Ogive and maybe sand the NC myself to get it more to scale?

Thanks for any help.

The ARCAS had the option of two nose cones; the No. 5A secant ogive and the No. 8 tangent ogive. Most common was the 5A. See the plan below.

AlphaSigOU said:

The ARCAS had the option of two nose cones; the No. 5A secant ogive and the No. 8 tangent ogive. Most common was the 5A. See the plan below.

Click to expand...

Chuck,

Excellent data . . . Hope all is well with you !

To OP - Note PDF file at bottom, too.

Dave Fitch

A few more items . . .

Dave F.